The Gherkin is reflected as window cleaners work on an office building in the City of London, Britain November 13, 2018. REUTERS/Toby Melville TPX IMAGES OF THE DAY 

A worker looks at their phone as they walk past The Gherkin, Lloyds, and other office buildings in the City of London, Britain November 13, 2018. REUTERS/Toby Melville 

The Gherkin is reflected as window cleaners work on an office building in the City of London, Britain November 13, 2018. REUTERS/Toby Melville 

A man speaks on his phone as he walks past The Gherkin and other office buildings in the City of London, Britain November 13, 2018. REUTERS/Toby Melville 

A man walks past The Gherkin and other office buildings in the City of London, Britain November 13, 2018. REUTERS/Toby Melville 

The Swiss Re building, known as the Gherkin (L), is seen in London, Britain, February 28, 2013. REUTERS/Stefan Wermuth/File Photo 

A British Union Jack flag and an European Union flag fly from a building, with the 'Gherkin' skyscraper seen in the City of London financial district in London, Britain, January 30, 2016. More Britons support the country's membership of the European Union than want to leave the bloc, the latest opinion poll on the issue showed on Saturday, even as opposition to membership grew slightly compared with last month's survey. REUTERS/Toby Melville 

A British Union Jack flag and an European Union flag fly from a building, with the 'Gherkin' and Leadenhall Building skyscrapers seen in the City of London financial district in London, Britain, January 30, 2016. More Britons support the country's membership of the European Union than want to leave the bloc, the latest opinion poll on the issue showed on Saturday, even as opposition to membership grew slightly compared with last month's survey. REUTERS/Toby Melville 

An employee is pictured in front of the 30 St Mary Axe skyscraper, which is known locally as "The Gherkin", as he rides an elevator on the exterior of the Lloyd's of London building in the City of London October 24, 2014. Britain still looks on track to outpace other advanced economies this year after rapid growth eased only slightly in the three months to September, but a euro zone slowdown could hamper the recovery in the run-up to next May's election. Official data on Friday showed the economy expanded by 0.7 percent in the third quarter, compared with 0.9 percent the quarter before - in line with forecasts in a Reuters poll. REUTERS/Toby Melville (BRITAIN - Tags: BUSINESS CITYSCAPE POLITICS) 

The 30 St Mary Axe skyscraper, which is known locally as "The Gherkin" and a building in which IWG (International Workplace Group) provides office space, is seen in London April 24, 2014. REUTERS/Stefan Wermuth 

The 30 St Mary Axe skyscraper, which is known locally as "The Gherkin" is seen in London April 24, 2014. London's landmark Gherkin office tower has been placed into receivership by its creditors, accountancy firm and joint receivers Deloitte said on Thursday, paving the way for a possible sale of the skyscraper. REUTERS/Stefan Wermuth (BRITAIN - Tags: BUSINESS REAL ESTATE) 

A worker walks past 30 St Mary Axe building, which is known locally as "The Gherkin", as he arrives for work at Lloyds of London February 28, 2014. London's financial services sector created 25 percent more jobs in February than a year ago, new data has shown, indicating the industry may be recovering from the restructuring and redundancies prompted by the financial crisis. After a strong January, the City hiring market showed no signs of slowing down last month, with 3,220 new jobs created, compared with 2,575 added in February 2013, according to financial services recruiter Astbury Marsden. The data suggests London's banks and financial services companies are returning to growth after slashing thousands of jobs in the face of a lengthy recession and a series of industry scandals that followed the financial crisis. Picture taken February 28, 2014. REUTERS/Eddie Keogh (BRITAIN - Tags: BUSINESS EMPLOYMENT)

ATTENTION EDITORS: PICTURE 09 OF 25 FOR PACKAGE 'CITY OF LONDON - LIFE IN THE SQUARE MILE'. TO FIND ALL IMAGES SEARCH 'RECRUITER KEOGH' 

A man is silhouetted as he passes the Swiss RE (known as the Gherkin) building in the City of London June 19, 2013. Britain should introduce laws making it possible to jail "reckless" bankers and claw back past bonus and pension awards, an influential panel of lawmakers said on Wednesday. REUTERS/Luke MacGregor (BRITAIN - Tags: BUSINESS CITYSCAPE POLITICS SOCIETY) 

The Swiss Re building, known as the Gherkin (L), is seen in the business district of the City of London February 28, 2013. A new cap on bankers' bonuses agreed overnight in Brussels was hailed by its supporters as a breakthrough to rein in the financial sector, but dismissed by critics as a reckless move that would drive bankers abroad or force up their base pay. REUTERS/Stefan Wermuth (BRITAIN - Tags: BUSINESS) 

A laser and searchlight show marks the completion of the exterior of the Shard building in central London on July 5, 2012. The 310-metre (1,016-feet) building, the tallest in western Europe, fired 12 lasers and 30 search lights from the top of the Shard to 15 London skyscrapers including the Gherkin and Canary Wharf. REUTERS/Olivia Harris (BRITAIN - Tags: SOCIETY BUSINESS CITYSPACE) 

A laser and searchlight show marks the completion of the exterior of the Shard building in central London on July 5, 2012. The 310-metre (1,016-feet) building, the tallest in western Europe, fired 12 lasers and 30 search lights from the top of the Shard to 15 London skyscrapers including the Gherkin and Canary Wharf. REUTERS/Olivia Harris (BRITAIN - Tags: SOCIETY CITYSPACE BUSINESS) 

The Shard glows red during the laser and searchlight show to mark the completion of the exterior of the Shard building in central London on July 5, 2012. The 310-metre (1,016-feet) building, the tallest in western Europe, fired 12 lasers and 30 search lights from the top of the Shard to 15 London skyscrapers including the Gherkin and Canary Wharf. REUTERS/Olivia Harris (BRITAIN - Tags: SOCIETY BUSINESS CITYSPACE) 

Laser beams are seen at the Shard during the laser and searchlight show which marks the completion of the exterior of the Shard building in central London July 5, 2012. The 310-metre (1,016-feet) building, the tallest in western Europe, fired 12 lasers and 30 searchlights from the top of the Shard to 15 London skyscrapers including the Gherkin and the Canary Wharf. REUTERS/Olivia Harris (BRITAIN - Tags: SOCIETY BUSINESS CONSTRUCTION CITYSPACE) 

A laser and searchlight show marks the completion of the exterior of the Shard building in central London July 5, 2012. The 310-metre (1,016-feet) building, the tallest in western Europe, fired 12 lasers and 30 searchlights from the top of the Shard to 15 London skyscrapers including the Gherkin and the Canary Wharf. REUTERS/Olivia Harris (BRITAIN - Tags: SOCIETY BUSINESS CONSTRUCTION CITYSPACE) 

A laser and searchlight show marks the completion of the exterior of the Shard building in central London July 5, 2012. The 310-metre (1,016-feet) building, the tallest in western Europe, fired 12 lasers and 30 searchlights from the top of the Shard to 15 London skyscrapers including the Gherkin and the Canary Wharf. REUTERS/Olivia Harris (BRITAIN - Tags: SOCIETY BUSINESS CONSTRUCTION CITYSPACE) 

A laser beam touches the Gherkin from the Shard during the laser and searchlight show which marks the completion of the exterior of the Shard building in central London July 5, 2012. The 310-metre (1,016-feet) building, the tallest in western Europe, fired 12 lasers and 30 searchlights from the top of the Shard to 15 London skyscrapers including the Gherkin and the Canary Wharf. REUTERS/Olivia Harris (BRITAIN - Tags: SOCIETY BUSINESS CONSTRUCTION CITYSPACE) 

A laser and searchlight show marks the completion of the exterior of the Shard building in central London July 5, 2012. The 310-metre (1,016-feet) building, the tallest in western Europe, fired 12 lasers and 30 searchlights from the top of the Shard to 15 London skyscrapers including the Gherkin and the Canary Wharf. REUTERS/Olivia Harris (BRITAIN - Tags: SOCIETY BUSINESS CONSTRUCTION) 

The City of London and the Swiss RE (known as the Gherkin) building and HMS Belfast are seen from the 69th floor of the Shard during its inauguration in London July 5, 2012. REUTERS/Luke MacGregor (BRITAIN - Tags: BUSINESS REAL ESTATE TRAVEL) 

A cameraman films a view of the City of London and the Swiss RE (known as the Gherkin) building from the 69th floor of the Shard during its inauguration in London July 5, 2012. REUTERS/Luke MacGregor (BRITAIN) 

The City of London and the Swiss RE (known as the Gherkin) is seen from the 69th floor of the Shard during its inauguration in London July 5, 2012. REUTERS/Luke MacGregor (BRITAIN - Tags: BUSINESS SOCIETY REAL ESTATE TRAVEL) 

The City of London and the Swiss RE (known as the Gherkin) is seen from the 69th floor of the Shard during its inauguration in London July 5, 2012. REUTERS/Luke MacGregor (BRITAIN - Tags: BUSINESS SOCIETY REAL ESTATE TRAVEL) 

Tower Bridge, Canary Wharf, HMS Belfast and the Swiss RE (known as the Gherkin) building are visible from the 69th floor of the Shard during its inauguration in London July 5, 2012. REUTERS/Luke MacGregor (BRITAIN - Tags: REAL ESTATE BUSINESS TRAVEL SOCIETY) 

The Swiss Re building, known as the "Gherkin", is seen behind a construction worker at Blackfriars Train Station in London February 15, 2012. The number of Britons out of work inched down in December from the 17-year high hit in November as employment rose and firms offered more jobs. REUTERS/Stefan Wermuth (BRITAIN - Tags: BUSINESS CONSTRUCTION EMPLOYMENT) 

The Swiss Re building, known as the "Gherkin", is seen behind construction workers at Blackfriars Train Station in London February 15, 2012. The number of Britons out of work inched down in December from the 17-year high hit in November as employment rose and firms offered more jobs. REUTERS/Stefan Wermuth (BRITAIN - Tags: BUSINESS CONSTRUCTION EMPLOYMENT) 

An Arriva London bus passes the Swiss Re building known as the Gherkin in the City of London December 9, 2011. Europe secured an historic agreement to draft a new treaty for deeper economic integration in the euro zone on Friday, but Britain, the region's third largest economy, refused to join the other 26 countries in a fiscal union and was isolated. REUTERS/Luke MacGregor (BRITAIN - Tags: POLITICS BUSINESS SOCIETY TRANSPORT TRAVEL) 

A City worker walks near the Swiss Re building known as the Gherkin in the City of London December 9, 2011. Europe secured an historic agreement to draft a new treaty for deeper economic integration in the euro zone on Friday, but Britain, the region's third largest economy, refused to join the other 26 countries in a fiscal union and was isolated. REUTERS/Luke MacGregor (BRITAIN) 

City workers cross London Bridge with the Swiss RE 'gherkin' building seen reflected in windows during the morning rush hour, in London April 11, 2011. Britain's top banks should shield their retail operations from riskier investment banking activities and hold more capital to protect taxpayers from any future financial crisis, a government-commissioned report said. British finance minister George Osborne said he welcomed the "excellent analysis" and findings of the commission led by former Bank of England interest rate setter John Vickers. REUTERS/Toby Melville (BRITAIN - Tags: BUSINESS) 

Competitors take part in the 'Step Change Challenge', a race up the 1037 steps of the 38 floors of the Gherkin building, to raise money for a charity, in London March 6, 2011. REUTERS/Stefan Wermuth (BRITAIN - Tags: SOCIETY SPORT) 

A worker smokes a cigar in the City of London February 9, 2011. Britain finalised a tortuous deal with banks on Wednesday to curb bonuses and boost lending to business, but critics said the agreement would be hard to enforce and mere "political theatre". REUTERS/Toby Melville (BRITAIN - Tags: BUSINESS) 

30 St Mary Axe, more commonly referred to as the 'Gherkin' office building, designed by Norman Foster, is seen reflected in another building in London, November 26, 2010. REUTERS/Toby Melville (BRITAIN - Tags: CITYSCAPE SOCIETY TRAVEL BUSINESS) 

30 St Mary Axe, more commonly referred to as the 'Gherkin' office building, designed by Norman Foster, is seen reflected in another building in London, November 26, 2010. REUTERS/Toby Melville (BRITAIN - Tags: CITYSCAPE SOCIETY TRAVEL BUSINESS) 

Dark clouds gather over 30 St. Mary Axe, formerly known as the Swiss RE building and also known as the Gherkin, in London August 12, 2010. REUTERS/Luke MacGregor (BRITAIN - Tags: BUSINESS) 

A woman looks out from an office block across from 30 St. Mary Axe, formerly known as the Swiss RE building and also known as the Gherkin, in London August 12, 2010. REUTERS/Luke MacGregor (BRITAIN - Tags: BUSINESS) 

A woman looks out from an office block across from 30 St. Mary Axe, formerly known as the Swiss RE building and also known as the Gherkin, in London August 12, 2010. REUTERS/Luke MacGregor (BRITAIN - Tags: BUSINESS) 

The City of London is seen beneath 30 St. Mary Axe, formerly known as the Swiss RE building and also known as the Gherkin, in London August 12, 2010. Financial markets regained some composure on Thursday after the previous session's broad selloff of riskier assets, with European shares inching up but the euro hurt by new worries about some of its weaker member economies. REUTERS/Luke MacGregor (BRITAIN - Tags: BUSINESS CITYSCAPE) 

A man passes the Swiss RE building, also known as the Gherkin, in the financial district City of London June 22, 2010. Britain's Chancellor of the Exchequer George Osborne announced the harshest budget in a generation on Tuesday, promising to bring a record budget deficit of 11 percent of GDP down to 1 percent in 5 years. REUTERS/Luke MacGregor (BRITAIN - Tags: BUSINESS POLITICS) 

The Swiss RE building, known as the Gherkin, is pictured from a nearby office block in the City of London April 7, 2010. The economy continued to recover in the first quarter of this year, a clutch of industry surveys showed on Wednesday, but concern about a public spending squeeze is making firms reluctant to invest. REUTERS/Luke MacGregor (BRITAIN - Tags: BUSINESS CITYSCAPE) 

Britain's Queen Elizabeth speaks with Lord Mayor of the City of London, Nick Anstee, as she attends a reception at the Swiss Re building - better known as The Gherkin - on her visit to the City of London February 24, 2010. REUTERS/Kirsty Wigglesworth/Pool (BRITAIN - Tags: ROYALS SOCIETY) 

Britain's Queen Elizabeth smiles as she attends a reception at the Swiss Re building - better known as The Gherkin - on her visit to the City of London February 24, 2010. REUTERS/Kirsty Wigglesworth/Pool (BRITAIN - Tags: ROYALS SOCIETY) 

Britain's Queen Elizabeth attends a reception at the Swiss Re building - better known as The Gherkin - on her visit to the City of London February 24, 2010. REUTERS/Kirsty Wigglesworth/Pool (BRITAIN - Tags: ROYALS SOCIETY) 

Britain's Queen Elizabeth attends a reception at the Swiss Re building - better known as The Gherkin - on her visit to the City of London February 24, 2010. REUTERS/Kirsty Wigglesworth/pool (BRITAIN - Tags: ROYALS SOCIETY) 

Britain's Queen Elizabeth looks upwards as she attends a reception at the Swiss Re building - better known as The Gherkin - on her visit to the City of London February 24, 2010. REUTERS/Kirsty Wigglesworth/Pool (BRITAIN - Tags: ROYALS SOCIETY) 

Britain's Queen Elizabeth looks upwards as she attends a reception at the Swiss Re building - better known as The Gherkin - on her visit to the City of London February 24, 2010. REUTERS/Kirsty Wigglesworth/Pool (BRITAIN - Tags: ROYALS SOCIETY) 

A statue of a First World War soldier stands in front of buildings, in the City of London February 16, 2010. British inflation surged further above the Bank of England's target in January, forcing Bank of England Governor Mervyn King to write a public letter where he said inflation should still get back on track later this year. . REUTERS/Toby Melville (BRITAIN - Tags: BUSINESS) 

Artist Vincent J.F. Huang's installation "Suicide Penguins", a comment on global warming, hangs below the Millennium Bridge in front of the Swiss RE building (known as the Gherkin) in London February 13, 2010. REUTERS/Luke MacGregor (BRITAIN - Tags: ENVIRONMENT SOCIETY ENTERTAINMENT) 

Pedestrians walk past the 'Gherkin' building in the City of London January 21, 2010. REUTERS/Luke MacGregor (BRITAIN - Tags: BUSINESS CITYSCAPE) 

A City worker is silhouetted in front of the 'Gherkin' building in the City of London January 21, 2010.
REUTERS/Luke MacGregor (BRITAIN - Tags: BUSINESS CITYSCAPE) 

A woman sunbathes on the South Bank in central London August 19, 2009. REUTERS/Luke MacGregor (BRITAIN ENVIRONMENT SOCIETY TRAVEL) 

The Canary Wharf financial district is seen behind the 'Gherkin' building in the City of London March 19, 2009. European banks took fresh steps to boost their balance sheets on Thursday, a day after UK regulators heralded tougher standards on capital adequacy and ahead of a finance-focussed G20 meeting of world leaders next month. REUTERS/Toby Melville (BRITAIN ENVIRONMENT BUSINESS POLITICS) 

Sunlight is reflected from Norman Foster's "Gherkin" as it stands among other buildings in the City of London, seen from the viewing platform of the Monument, in the City of London February 16, 2009. The Monument, is the tallest free standing stone column in the world and was built to commemorate the Great Fire of London. The Monument was reopened to the public on Monday after an extensive restoration. REUTERS/Andrew Winning (BRITAIN) 

A man walks through the financial district of London September 19, 2008. Britain's top share index soared 7.8 percent by midday on Friday to snap a four-day losing run, as banks rebounded sharply on a radical U.S. government plan aimed at tackling the crisis besieging financial markets. REUTERS/Stephen Hird (BRITAIN) 

A weather vane is pictured in front of the Swiss RE 'Gherkin' building in the financial district of London September 19, 2008. Britain's top share index soared 7.8 percent by midday on Friday to snap a four-day losing run, as banks rebounded sharply on a radical U.S. government plan aimed at tackling the crisis besieging financial markets. REUTERS/Stephen Hird (BRITAIN) 

The Swiss RE 'Gherkin' building is seen in the city of London September 17, 2008. REUTERS/Toby Melville (BRITAIN) 

People walk past Tower 42 (L) and the Swiss Re "Gherkin" building as they walk across Waterloo Bridge during the morning rush hour in London September 17, 2008. REUTERS/Toby Melville (BRITAIN) 

Passengers on a London bus ride past the Swiss RE 'Gherkin' building as it crosses Waterloo Bridge in the city of London September 17, 2008. REUTERS/Toby Melville (BRITAIN)