The new leader of Britain's opposition Labour Party Jeremy Corbyn addresses the Trade Union Congress (TUC) in Brighton in southern England, September 15, 2015. REUTERS/Peter Nicholls 

The new leader of Britain's opposition Labour Party Jeremy Corbyn addresses the Trade Union Congress (TUC) in Brighton in southern England, September 15, 2015. REUTERS/Peter Nicholls 

The new leader of Britain's opposition Labour Party Jeremy Corbyn addresses the Trade Union Congress (TUC) in Brighton in southern England, September 15, 2015. REUTERS/Peter Nicholls 

The new leader of Britain's opposition Labour Party Jeremy Corbyn addresses the Trade Union Congress (TUC) in Brighton in southern England, September 15, 2015. REUTERS/Peter Nicholls 

The new leader of Britain's opposition Labour Party Jeremy Corbyn gestures as he aknowledges applause after addressing the Trade Union Congress (TUC) in Brighton in southern England, September 15, 2015. REUTERS/Peter Nicholls 

The new leader of Britain's opposition Labour Party Jeremy Corbyn gestures as he aknowledges applause after addressing the Trade Union Congress (TUC) in Brighton in southern England, September 15, 2015. REUTERS/Peter Nicholls 

The new leader of Britain's opposition Labour Party Jeremy Corbyn gestures as he aknowledges applause after addressing the Trade Union Congress (TUC) in Brighton in southern England, September 15, 2015. REUTERS/Peter Nicholls 

The new leader of Britain's opposition Labour Party Jeremy Corbyn gestures as he aknowledges applause after addressing the Trade Union Congress (TUC) in Brighton in southern England, September 15, 2015. REUTERS/Peter Nicholls 

The new leader of Britain's opposition Labour Party Jeremy Corbyn gestures as he aknowledges applause after addressing the Trade Union Congress (TUC) in Brighton in southern England, September 15, 2015. REUTERS/Peter Nicholls 

The new leader of Britain's opposition Labour Party Jeremy Corbyn addresses the Trade Union Congress (TUC) in Brighton in southern England, September 15, 2015. REUTERS/Peter Nicholls 

The new leader of Britain's opposition Labour Party Jeremy Corbyn addresses the Trade Union Congress (TUC) in Brighton in southern England, September 15, 2015. REUTERS/Peter Nicholls 

The new leader of Britain's opposition Labour Party Jeremy Corbyn aknowledges applause before addressing the Trade Union Congress (TUC) in Brighton in southern England, September 15, 2015. REUTERS/Peter Nicholls 

The new leader of Britain's opposition Labour Party Jeremy Corbyn prepares to address the Trade Union Congress (TUC) in Brighton in southern England, September 15, 2015. REUTERS/Peter Nicholls 

The new leader of Britain's opposition Labour Party Jeremy Corbyn addresses the Trade Union Congress (TUC) in Brighton in southern England, September 15, 2015. REUTERS/Peter Nicholls 

The new leader of Britain's opposition Labour Party Jeremy Corbyn addresses the Trade Union Congress (TUC) in Brighton in southern England, September 15, 2015. REUTERS/Peter Nicholls 

The new leader of Britain's opposition Labour Party Jeremy Corbyn addresses the Trade Union Congress (TUC) in Brighton in southern England, September 15, 2015. REUTERS/Peter Nicholls 

The new leader of Britain's opposition Labour Party Jeremy Corbyn addresses the Trade Union Congress (TUC) in Brighton in southern England, September 15, 2015. REUTERS/Peter Nicholls 

The new leader of Britain's opposition Labour Party Jeremy Corbyn addresses the Trade Union Congress (TUC) in Brighton in southern England, September 15, 2015. REUTERS/Peter Nicholls 

The new leader of Britain's opposition Labour Party Jeremy Corbyn addresses the Trade Union Congress (TUC) in Brighton in southern England, September 15, 2015. REUTERS/Peter Nicholls 

Donations of cash are counted following a collection for the Greek Solidarity Campaign, during a rally in support of Greece at the TUC's Congress House, in London, Britain, July 6, 2015. REUTERS/Peter Nicholls

Volunteers make a collection for the Greek Solidarity Campaign, during a rally in support of Greece at the TUC's Congress House, in London, Britain, July 6, 2015. REUTERS/Peter Nicholls

Donations of cash are counted following a collection for the Greek Solidarity Campaign, during a rally in support of Greece at the TUC's Congress House, in London, Britain, July 6, 2015. REUTERS/Peter Nicholls

Donations of cash are counted following a collection for the Greek Solidarity Campaign, during a rally in support of Greece at the TUC's Congress House, in London, Britain, July 6, 2015. REUTERS/Peter Nicholls

A man adds his name to a petition to cancel Greek debt during a rally in support of Greece at the TUC's Congress House, in London, Britain, July 6, 2015. REUTERS/Peter Nicholls

Trades Union Congress (TUC) General Secretary Frances O'Grady holds a placard as she joins strikers outside St Pancras Hospital in London October 13, 2014. Thousands of health workers in Britain went on strike on Monday to protest against a pay freeze, the first walk out over pay in the country's state-run National Health Service (NHS) for over thirty years. REUTERS/Stefan Wermuth (BRITAIN - Tags: HEALTH POLITICS) 

Trades Union Congress (TUC) General Secretary Frances O'Grady joins strikers outside St Pancras Hospital in London October 13, 2014. Thousands of health workers in Britain went on strike on Monday to protest against a pay freeze, the first walk out over pay in the country's state-run National Health Service (NHS) for over thirty years. REUTERS/Stefan Wermuth (BRITAIN - Tags: HEALTH POLITICS) 

Bank of England Governor Mark Carney (L) listens to Trades Union Congress (TUC) general secretary Frances O'Grady before his keynote speech at the annual TUC conference, in Liverpool, northern England September 9, 2014. REUTERS/Phil Noble (BRITAIN - Tags: BUSINESS POLITICS) 

Bank of England Governor Mark Carney waits to deliver his keynote speech at the annual Trades Union Congress (TUC), in Liverpool, northern England September 9, 2014. REUTERS/Phil Noble (BRITAIN - Tags: BUSINESS POLITICS) 

Bank of England Governor Mark Carney delivers his keynote speech at the annual Trades Union Congress (TUC), in Liverpool, northern England September 9, 2014. REUTERS/Phil Noble (BRITAIN - Tags: BUSINESS POLITICS) 

Bank of England Governor Mark Carney delivers his keynote speech at the annual Trades Union Congress (TUC), in Liverpool, northern England September 9, 2014. REUTERS/Phil Noble (BRITAIN - Tags: BUSINESS POLITICS) 

Bank of England Governor Mark Carney delivers his keynote speech at the annual Trades Union Congress (TUC), in Liverpool, northern England September 9, 2014. REUTERS/Phil Noble (BRITAIN - Tags: BUSINESS POLITICS) 

Bank of England Governor Mark Carney delivers his keynote speech at the annual Trades Union Congress (TUC), in Liverpool, northern England September 9, 2014. REUTERS/Phil Noble (BRITAIN - Tags: BUSINESS POLITICS) 

Bank of England Governor Mark Carney delivers his keynote speech at the annual Trades Union Congress (TUC), in Liverpool, northern England September 9, 2014. REUTERS/Phil Noble (BRITAIN - Tags: BUSINESS POLITICS) 

Bank of England Governor Carney delivers his keynote speech at the annual Trades Union Congress (TUC), in Liverpool, northern England September 9, 2014. REUTERS/Phil Noble (BRITAIN - Tags: BUSINESS POLITICS) 

Tins of sweets with an image of communist leader Vladimir Lenin are seen for sale on a stall at the annual Trades Union Congress (TUC), in Liverpool, northern England September 9, 2014. REUTERS/Phil Noble (BRITAIN - Tags: POLITICS BUSINESS EMPLOYMENT) 

Novelty mugs are displayed for sale on a stand at the Trades Union Congress (TUC) in Liverpool, northern England September 9, 2014. REUTERS/Phil Noble (BRITAIN - Tags: BUSINESS EMPLOYMENT POLITICS) 

Novelty mugs bearing a photograph of former British Prime Minister Margaret Thatcher are displayed for sale on a stand at the Trades Union Congress (TUC) in Liverpool, northern England September 9, 2014. REUTERS/Phil Noble (BRITAIN - Tags: BUSINESS EMPLOYMENT POLITICS) 

Novelty coasters are displayed for sale on a stand at the Trades Union Congress (TUC) in Liverpool, northern England September 9, 2014. REUTERS/Phil Noble (BRITAIN - Tags: BUSINESS EMPLOYMENT POLITICS) 

Frances O'Grady (R), General Secretary of the Trades Union Congress (TUC), smiles after delivering her keynote speech at their annual conference, in Liverpool, northern England September 8, 2014. REUTERS/Phil Noble (BRITAIN - Tags: BUSINESS EMPLOYMENT POLITICS) 

Dave Prentis, secretary general of the Unison Union, speaks at the Trades Union Congress (TUC) annual conference, in Liverpool, northern England September 8, 2014. REUTERS/Phil Noble (BRITAIN - Tags: BUSINESS EMPLOYMENT POLITICS) 

Frances O'Grady, General Secretary of the Trades Union Congress (TUC), gestures as she delivers her keynote speech at their annual conference, in Liverpool, northern England September 8, 2014. REUTERS/Phil Noble (BRITAIN - Tags: BUSINESS EMPLOYMENT POLITICS) 

Frances O'Grady, General Secretary of the Trades Union Congress (TUC), delivers her keynote speech at their annual conference, in Liverpool, northern England September 8, 2014. REUTERS/Phil Noble (BRITAIN - Tags: BUSINESS EMPLOYMENT POLITICS) 

Frances O'Grady, General Secretary of the Trades Union Congress (TUC), delivers her keynote speech at their annual conference, in Liverpool, northern England September 8, 2014. REUTERS/Phil Noble (BRITAIN - Tags: BUSINESS EMPLOYMENT POLITICS) 

Frances O'Grady, General Secretary of the Trades Union Congress (TUC), delivers her keynote speech at their annual conference, in Liverpool, northern England September 8, 2014. REUTERS/Phil Noble (BRITAIN - Tags: BUSINESS EMPLOYMENT POLITICS) 

A dog wears an anti-nuclear missile banner that reads "No Nukes", as it stands with its owner outside the annual Trades Union Congress (TUC), in Liverpool, northern England September 8, 2014. REUTERS/Phil Noble (BRITAIN - Tags: ANIMALS CONFLICT POLITICS) 

Britain's opposition Labour leader Ed Miliband leaves the Trades Unions Congress (TUC) in Bournemouth, southern England September 10, 2013. REUTERS/Luke MacGregor (BRITAIN - Tags: POLITICS BUSINESS EMPLOYMENT) 

Britain's opposition Labour leader Ed Miliband arrives at the Trades Union Congress (TUC) in Bournemouth, southern England September 10, 2013. REUTERS/Luke MacGregor (BRITAIN - Tags: POLITICS BUSINESS EMPLOYMENT) 

GMB general secretary Paul Kenny listens as Britain's opposition Labour leader Ed Miliband addresses the Trades Union Congress (TUC) in Bournemouth, southern England September 10, 2013. REUTERS/Luke MacGregor (BRITAIN - Tags: POLITICS BUSINESS EMPLOYMENT) 

Novelty mugs are displayed for sale on a stand at the Trades Union Congress (TUC) in Bournemouth, southern England September 10, 2013. REUTERS/Luke MacGregor (BRITAIN - Tags: POLITICS BUSINESS EMPLOYMENT) 

Britain's opposition Labour leader Ed Miliband waves to delegates after addressing the Trades Union Congress (TUC) in Bournemouth, southern England September 10, 2013. REUTERS/Luke MacGregor (BRITAIN - Tags: POLITICS BUSINESS EMPLOYMENT) 

Britain's opposition Labour leader Ed Miliband addresses the Trades Union Congress (TUC) in Bournemouth, southern England September 10, 2013. REUTERS/Luke MacGregor (BRITAIN - Tags: POLITICS BUSINESS EMPLOYMENT) 

Britain's opposition Labour leader Ed Miliband addresses the Trades Union Congress (TUC) in Bournemouth, southern England September 10, 2013. REUTERS/Luke MacGregor (BRITAIN - Tags: POLITICS BUSINESS EMPLOYMENT) 

Britain's opposition Labour leader Ed Miliband waits to make his address to the Trades Union Congress (TUC) in Bournemouth, southern England September 10, 2013. REUTERS/Luke MacGregor (BRITAIN - Tags: POLITICS BUSINESS EMPLOYMENT) 

Britain's opposition Labour leader Ed Miliband addresses the Trades Union Congress (TUC) in Bournemouth, southern England September 10, 2013. REUTERS/Luke MacGregor (BRITAIN - Tags: POLITICS BUSINESS EMPLOYMENT) 

Britain's opposition Labour leader Ed Miliband (L) addresses the Trades Union Congress (TUC) in Bournemouth, southern England September 10, 2013. REUTERS/Luke MacGregor (BRITAIN - Tags: POLITICS BUSINESS EMPLOYMENT) 

Britain's opposition Labour leader Ed Miliband addresses the Trades Union Congress (TUC) in Bournemouth, southern England September 10, 2013. REUTERS/Luke MacGregor (BRITAIN - Tags: POLITICS BUSINESS EMPLOYMENT) 

Britain's opposition Labour leader Ed Miliband addresses the Trades Union Congress (TUC) in Bournemouth, southern England September 10, 2013. REUTERS/Luke MacGregor (BRITAIN - Tags: POLITICS BUSINESS EMPLOYMENT TPX IMAGES OF THE DAY) 

Britain's opposition Labour leader Ed Miliband addresses the Trades Union Congress (TUC) in Bournemouth, southern England September 10, 2013. REUTERS/Luke MacGregor (BRITAIN - Tags: POLITICS BUSINESS EMPLOYMENT)