German Transport Minister Andreas Scheuer adjusts his tie during a high level conference of the air traffic industry to discuss air travel in the coronavirus pandemic and the path to sustainable flying at the BER Airport in Berlin Schoenefeld, Germany, June 18, 2021. Soeren Stache/Pool via REUTERS

German Transport Minister Andreas Scheuer poses in front of an engine of an Airbus A 320neo during a high level conference of the air traffic industry to discuss air travel in the coronavirus pandemic and the path to sustainable flying at the BER Airport in Berlin Schoenefeld, Germany, June 18, 2021. Soeren Stache/Pool via REUTERS

German Transport Minister Andreas Scheuer and Lufthansa CEO Carsten Spohr pose in front of an Airbus A 320neo during a high level conference of the air traffic industry to discuss air travel in the coronavirus pandemic and the path to sustainable flying at the BER Airport in Berlin Schoenefeld, Germany, June 18, 2021. Soeren Stache/Pool via REUTERS

German Transport Minister Andreas Scheuer and Lufthansa CEO Carsten Spohr pose in front of an engine of an Airbus A 320neo during a high level conference of the air traffic industry to discuss air travel in the coronavirus pandemic and the path to sustainable flying at the BER Airport in Berlin Schoenefeld, Germany, June 18, 2021. Soeren Stache/Pool via REUTERS

German Transport Minister Andreas Scheuer and Lufthansa CEO Carsten Spohr pose in front of an engine of an Airbus A 320neo during a high level conference of the air traffic industry to discuss air travel in the coronavirus pandemic and the path to sustainable flying at the BER Airport in Berlin Schoenefeld, Germany, June 18, 2021. Soeren Stache/Pool via REUTERS

German Transport Minister Andreas Scheuer and Lufthansa CEO Carsten Spohr pose on board of an Airbus A 320neo during a high level conference of the air traffic industry to discuss air travel in the coronavirus pandemic and the path to sustainable flying at the BER Airport in Berlin Schoenefeld, Germany, June 18, 2021. Soeren Stache/Pool via REUTERS

German Transport Minister Andreas Scheuer and Lufthansa CEO Carsten Spohr pose on board of an Airbus A 320neo during a high level conference of the air traffic industry to discuss air travel in the coronavirus pandemic and the path to sustainable flying at the BER Airport in Berlin Schoenefeld, Germany, June 18, 2021. Soeren Stache/Pool via REUTERS

German Transport Minister Andreas Scheuer and Lufthansa CEO Carsten Spohr pose on board of an Airbus A 320neo during a high level conference of the air traffic industry to discuss air travel in the coronavirus pandemic and the path to sustainable flying at the BER Airport in Berlin Schoenefeld, Germany, June 18, 2021. Soeren Stache/Pool via REUTERS

German Transport Minister Andreas Scheuer and Lufthansa CEO Carsten Spohr pose on board of an Airbus A 320neo during a high level conference of the air traffic industry to discuss air travel in the coronavirus pandemic and the path to sustainable flying at the BER Airport in Berlin Schoenefeld, Germany, June 18, 2021. Soeren Stache/Pool via REUTERS

German Transport Minister Andreas Scheuer holds a bike bag as birthday present for Economy Minister Peter Altmaier during a high level conference of the air traffic industry to discuss air travel in the coronavirus pandemic and the path to sustainable flying at the BER Airport in Berlin Schoenefeld, Germany, June 18, 2021. Soeren Stache/Pool via REUTERS

German Transport Minister Andreas Scheuer listens to German Chancellor Angela Merkel appearing on a video screen during a high level conference of the air traffic industry to discuss air travel in the coronavirus pandemic and the path to sustainable flying at the BER Airport in Berlin Schoenefeld, Germany, June 18, 2021. Soeren Stache/Pool via REUTERS

A protester holds a flag as he sits on a traffic light post during a pro-Palestine demonstration outside Downing Street in London, Britain, June 12, 2021. REUTERS/Henry Nicholls

A protester holds a flag as he sits on a traffic light post during a pro-Palestine demonstration outside Downing Street in London, Britain, June 12, 2021. REUTERS/Henry Nicholls

A protester has climbed a traffic light pole during a pro-Palestine demonstration outside Downing Street in London, Britain, June 12, 2021. REUTERS/Henry Nicholls

A man walks holding a liquor bottle as a NYPD traffic officer passes by near Times Square in New York City, U.S., June 11, 2021. Picture taken June 11, 2021. REUTERS/Shannon Stapleton

A man sits in a wheelchair as a NYPD traffic officer passes by near Times Square in New York City, U.S., June 11, 2021. Picture taken June 11, 2021. REUTERS/Shannon Stapleton

A sign warning drivers to drive on the left hand side of the road is seen near a memorial area for British teenager Harry Dunn who died in a road traffic collision, near to the entrance of RAF Croughton, in Croughton, near Brackley, Britain June 11, 2021. REUTERS/Andrew Boyers

A rose is pictured on top of a banner and a memorial area for British teenager Harry Dunn who died in a road traffic collision, near to the entrance of RAF Croughton, in Croughton, near Brackley, Britain June 11, 2021. REUTERS/Andrew Boyers

A banner and a memorial area for British teenager Harry Dunn who died in a road traffic collision is pictured near to the entrance of RAF Croughton, in Croughton, near Brackley, Britain June 11, 2021. REUTERS/Andrew Boyers

A banner and a memorial area for British teenager Harry Dunn who died in a road traffic collision is pictured near to the entrance of RAF Croughton, in Croughton, near Brackley, Britain June 11, 2021. REUTERS/Andrew Boyers

A banner and a memorial area for British teenager Harry Dunn who died in a road traffic collision is pictured near to the entrance of RAF Croughton, in Croughton, near Brackley, Britain June 11, 2021. REUTERS/Andrew Boyers

The logo of Toshiba Corp. is seen next to a traffic signal atop of a building in Tokyo, Japan June 11, 2021. REUTERS/Issei Kato

The logo of Toshiba Corp. is seen next to a traffic signal atop of a building in Tokyo, Japan June 11, 2021. REUTERS/Issei Kato

The logo of Toshiba Corp. is seen next to a traffic signal atop of a building in Tokyo, Japan June 11, 2021. REUTERS/Issei Kato

A view shows cars stuck in a traffic jam in Beirut, Lebanon June 10, 2021. Picture taken June 10, 2021. REUTERS/Mohamed Azakir

A view shows cars stuck in a traffic jam in Beirut, Lebanon June 10, 2021. Picture taken June 10, 2021. REUTERS/Mohamed Azakir

Cars and motorbikes wait at the traffic lights during rush hour in front of a Taiwan Semiconductor Manufacturing Co (TSMC) office building, in Hsinchu, Taiwan, June 8, 2021. REUTERS/Ann Wang

Traffic moves on a flyover, after authorities eased lockdown restrictions that were imposed to slow the spread of the coronavirus disease (COVID-19), in New Delhi, India, June 8, 2021. REUTERS/Adnan Abidi

A Cessna passes between the Tower Tech Inc. mobile air traffic tower and U.S. Air Force C-17 airplanes at Sacramento McClellan Airport in Sacramento, California, U.S., June 5, 2021. Picture taken June 5, 2021. REUTERS/Tracy Barbutes

Tower Tech Inc. founder, Titus "Stretch" Gall, uses binoculars to scan the skyline from his mobile air traffic control tower while on contract with Sacramento McClellan Airport in Sacramento, California, U.S., June 5, 2021. Picture taken June 5, 2021. REUTERS/Tracy Barbutes

Tower Tech Inc. founder, Titus "Stretch" Gall, talks to pilots via radio from his mobile air traffic control tower as U.S. Air Force C-17 airplanes fly overhead at Sacramento McClellan Airport in Sacramento, California, U.S., June 5, 2021. Picture taken June 5, 2021. REUTERS/Tracy Barbutes

A U.S. Air Force C-17 makes its final approach at Sacramento McClellan Airport while speaking with Tower Tech Inc. air traffic controllers, in Sacramento, California, U.S., June 5, 2021. Picture taken June 5, 2021. REUTERS/Tracy Barbutes

People wearing face masks wait at a traffic junction as Mexico City's authorities announce a full reopening of the city come Monday, the first time since the coronavirus disease (COVID-19) pandemic, Mexico June 4, 2021. REUTERS/Edgard Garrido

Tower Tech Inc. founder, Titus "Stretch" Gall, stands near his mobile tower at Sacramento McClellan Airport in Sacramento, California, U.S., June 3, 2021. Picture taken June 3, 2021. REUTERS/Tracy Barbutes

Tower Tech Inc. founder, Titus "Stretch" Gall, attaches a rooftop antenna on his mobile air traffic control tower parked at Sacramento McClellan Airport in Sacramento, California, U.S., June 3, 2021. Picture taken June 3, 2021. REUTERS/Tracy Barbutes

Tower Tech Inc. founder, Titus "Stretch" Gall, hauls his mobile air traffic control tower onto the Sacramento McClellan Airport in Sacramento, California, U.S., June 3, 2021. Picture taken June 3, 2021. REUTERS/Tracy Barbutes

A radio sits on a counter in a Tower Tech Inc. mobile air traffic control tower at Sacramento McClellan Airport in Sacramento, California, U.S., June 3, 2021. Picture taken June 3, 2021. REUTERS/Tracy Barbutes

U.S. Secretary of Transportation Pete Buttigieg tours the closed Hernando De Soto bridge which carries Interstate 40 across the Mississippi River between West Memphis, Arkansas, and Memphis, Tennessee, U.S. June 3, 2021. The bridge has been shut down, halting traffic on the thoroughfare since May 11, 2021 after a fracture was discovered. Joe Rondone/The Commercial Appeal/Pool via REUTERS TPX IMAGES OF THE DAY

U.S. Secretary of Transportation Pete Buttigieg tours the closed Hernando De Soto bridge which carries Interstate 40 across the Mississippi River between West Memphis, Arkansas, and Memphis, Tennessee, U.S. June 3, 2021. The bridge has been shut down, halting traffic on the thoroughfare since May 11, 2021 after a fracture was discovered. Joe Rondone/The Commercial Appeal/Pool via REUTERS

Cars are seen in a traffic jam in central Kyiv, Ukraine June 1, 2021. REUTERS/Gleb Garanich

Traffic is seen along the Strip on Memorial Day in Las Vegas, Nevada, U.S., May 31, 2021. REUTERS/Bridget Bennett

People riding bicycles and motorbikes wait in traffic, amid the coronavirus disease (COVID-19) pandemic, in Shanghai, China May 31, 2021. REUTERS/Aly Song

A demonstrator climbs traffic lights during a protest demanding government action to tackle poverty, police violence and inequalities in healthcare and education systems, in Bogota, Colombia, May 28, 2021. REUTERS/Luisa Gonzalez TPX IMAGES OF THE DAY

Vehicles are seen in traffic jam during afternoon rush hour in Jakarta, Indonesia, May 27, 2021. REUTERS/Willy Kurniawan

Vehicles are seen in traffic jam during afternoon rush hour in Jakarta, Indonesia, May 27, 2021. REUTERS/Willy Kurniawan

A Palestinian policeman directs traffic near a building damaged in Israeli missile strikes in the recent cross-border violence between Palestinian militants and Israel, following Israel-Hamas truce, in Gaza City May 21, 2021. REUTERS/Mohammed Salem

Demonstrators try to knock down a traffic light during a protest demanding government action to tackle poverty, police violence and inequalities in healthcare and education systems, in Medellin, Colombia, May 18, 2021. REUTERS/Santiago Mesa

Special Constable Rosen turns back traffic after the city of Prince Albert declared a state of emergency over a fast-moving wildfire, prompting some residents to evacuate, in Prince Albert, Saskatchewan, Canada May 18, 2021. REUTERS/David Stobbe

People walk past a traffic direction sign for clients in the Westfield Forum des Halles shopping centre during preparations for the reopening of shops in Paris as part of an easing of the country's lockdown restrictions amid the coronavirus disease (COVID-19) outbreak in France, May 18, 2021. REUTERS/Sarah Meyssonnier

People riding motorcycles and wearing protective face masks wait at a traffic stop, amid a surge in coronavirus disease (COVID-19) infections in Taipei, Taiwan May 18, 2021. REUTERS/Ann Wang

A Palestinian flag flutters at a traffic circle in the Arab city of Nazareth, Israel May 13, 2021. REUTERS/Rami Ayyub

Soccer Football - Premier League - Manchester United v Liverpool - Old Trafford, Manchester, Britain - May 13, 2021 A fan on top of traffic lights with a flare as Manchester United fans protest against their owners outside the stadium before the match Action Images via Reuters/Molly Darlington

Soccer Football - Premier League - Manchester United v Liverpool - Old Trafford, Manchester, Britain - May 13, 2021 A fan on top of traffic lights as Manchester United fans protest against their owners outside the stadium before the match Action Images via Reuters/Molly Darlington

Cyclists take part in a commemoration ceremony for their colleague who was hit by a car, during a protest demanding the construction of bicycle lanes and tightening traffic rules and reminder about 235 cyclists who died in 2020, in front of the City Hall in central Kyiv, Ukraine May 13, 2021. REUTERS/Gleb Garanich

Cyclists take part in a commemoration ceremony for their colleague who was hit by a car, during a protest demanding the construction of bicycle lanes and tightening traffic rules and reminder about 235 cyclists who died in 2020, in front of the City Hall in central Kyiv, Ukraine May 13, 2021. REUTERS/Gleb Garanich

Cyclists embrace as they take part in a commemoration ceremony for their colleague who was hit by a car, during a protest demanding the construction of bicycle lanes and tightening traffic rules and reminder about 235 cyclists who died in 2020, in front of the City Hall in central Kyiv, Ukraine May 13, 2021. REUTERS/Gleb Garanich

Flowers are seen as cyclists take part in a commemoration ceremony for their colleague who was hit by a car, during a protest demanding the construction of bicycle lanes and tightening traffic rules and reminder about 235 cyclists who died in 2020, in front of the City Hall in central Kyiv, Ukraine May 13, 2021. REUTERS/Gleb Garanich

The logo of Spanish Telecom company Telefonica is seen next to a traffic ligth at its headquarters in Madrid, Spain, May 12, 2021. REUTERS/Sergio Perez

A line of vehicles proceeds towards a gas pumps at Costco, as Eric Howard directs traffic, after a cyberattack crippled the biggest fuel pipeline in the country, run by Colonial Pipeline, in Norfolk, Virginia, U.S. May 11, 2021. REUTERS/Jay Paul

A line of vehicles proceeds towards gas pumps at Costco, as Eric Howard directs traffic after a cyberattack crippled the biggest fuel pipeline in the country, run by Colonial Pipeline, in Norfolk, Virginia, U.S., May 11, 2021. REUTERS/Jay Paul