A Malaysia Airlines plane carrying the first batch of tourists arrives at the airport as Langkawi reopens to domestic tourists, amid the coronavirus disease (COVID-19) pandemic, in Malaysia September 16, 2021. REUTERS/Lim Huey Teng

A Malaysia Airlines plane carrying the first batch of tourists receives a water cannon salute from water trucks as Langkawi reopens to domestic tourists, amid the coronavirus disease (COVID-19) pandemic in Malaysia September 16, 2021. REUTERS/Lim Huey Teng

U.S. first lady Jill Biden waves from her plane as she departs from Des Moines International Airport, Iowa, U.S., September 15, 2021. REUTERS/Evelyn Hockstein/Pool

U.S. first lady Jill Biden boards her plane as she departs from Des Moines International Airport, Iowa, U.S., September 15, 2021. REUTERS/Evelyn Hockstein/Pool

U.S. first lady Jill Biden boards her plane at Des Moines International Airport, Iowa, U.S., September 15, 2021. REUTERS/Evelyn Hockstein/Pool

U.S. first lady Jill Biden walks next to local police escort before boarding a plane at General Mitchell International Airport, in Milwaukee, Wisconsin, U.S., September 15, 2021. REUTERS/Evelyn Hockstein/Pool TPX IMAGES OF THE DAY

U.S. first lady Jill Biden walks near to local police escort before boarding a plane, in Milwaukee, Wisconsin, U.S., September 15, 2021. REUTERS/Evelyn Hockstein/Pool

U.S. first lady Jill Biden greets local police escort on motorcycle, before boarding a plane at General Mitchell International Airport in Milwaukee, Wisconsin, U.S., September 15, 2021. REUTERS/Evelyn Hockstein/Pool

U.S. first lady Jill Biden waves as she boards a plane at General Mitchell International Airport in Milwaukee, Wisconsin, U.S., September 15, 2021. REUTERS/Evelyn Hockstein/Pool

U.S. first lady Jill Biden walks near to the local motorcycle police escort before boarding a plane, in Milwaukee, Wisconsin, U.S., September 15, 2021. REUTERS/Evelyn Hockstein/Pool

Canada's Liberal Prime Minister Justin Trudeau boards his campaign plane with Dominic Leblanc, Minister of Intergovernmental Affairs, in Halifax, Nova Scotia, Canada September 15, 2021. REUTERS/Carlos Osorio

Canada's Liberal Prime Minister Justin Trudeau boards his campaign plane with Dominic Leblanc, Minister of Intergovernmental Affairs, in Halifax, Nova Scotia, Canada September 15, 2021. REUTERS/Carlos Osorio

Canada's Liberal Prime Minister Justin Trudeau boards his campaign plane in Halifax, Nova Scotia, Canada September 15, 2021. REUTERS/Carlos Osorio

Canada's Liberal Prime Minister Justin Trudeau on board his campaign plane with his Chief of Staff, Katie Telford, after a campaign stop in Brampton, Ontario, Canada, September 14, 2021. REUTERS/Carlos Osorio

A plane flies past a high-tension electricity tower on the outskirts of Madrid, Spain, September 14, 2021. REUTERS/Susana Vera

A view from a transport military plane shows Russian airborne combat vehicles descending beneath parachutes during the exercises "Zapad-2021" staged by the armed forces of Russia and Belarus in Kaliningrad Region, Russia, September 13, 2021. REUTERS/Vitaly Nevar

Russian paratroopers sit inside an Ilyushin Il-76 transport plane before their departure during the military exercises "Zapad-2021" staged by the armed forces of Russia and Belarus at an aerodrome in Kaliningrad Region, Russia, September 13, 2021. REUTERS/Vitaly Nevar

Russian paratroopers board an Ilyushin Il-76 transport plane as they take part in the military exercises "Zapad-2021" staged by the armed forces of Russia and Belarus at an aerodrome in Kaliningrad Region, Russia, September 13, 2021. REUTERS/Vitaly Nevar

Russian paratroopers board an Ilyushin Il-76 transport plane as they take part in the military exercises "Zapad-2021" staged by the armed forces of Russia and Belarus at an aerodrome in Kaliningrad Region, Russia, September 13, 2021. REUTERS/Vitaly Nevar

Russian paratroopers line up before boarding an Ilyushin Il-76 transport plane as they take part in the military exercises "Zapad-2021" staged by the armed forces of Russia and Belarus at an aerodrome in Kaliningrad Region, Russia, September 13, 2021. REUTERS/Vitaly Nevar

Russian paratroopers walk before boarding Ilyushin Il-76 transport planes as they take part in the military exercises "Zapad-2021" staged by the armed forces of Russia and Belarus at an aerodrome in Kaliningrad Region, Russia, September 13, 2021. REUTERS/Vitaly Nevar

Russian paratroopers wait before boarding Ilyushin Il-76 transport planes as they take part in the military exercises "Zapad-2021" staged by the armed forces of Russia and Belarus at an aerodrome in Kaliningrad Region, Russia, September 13, 2021. REUTERS/Vitaly Nevar

Russian paratroopers walk before boarding Ilyushin Il-76 transport planes as they take part in the military exercises "Zapad-2021" staged by the armed forces of Russia and Belarus at an aerodrome in Kaliningrad Region, Russia, September 13, 2021. REUTERS/Vitaly Nevar

Russian paratroopers wait before boarding Ilyushin Il-76 transport planes as they take part in the military exercises "Zapad-2021" staged by the armed forces of Russia and Belarus at an aerodrome in Kaliningrad Region, Russia, September 13, 2021. REUTERS/Vitaly Nevar

Russian paratroopers wait before boarding Ilyushin Il-76 transport planes as they take part in the military exercises "Zapad-2021" staged by the armed forces of Russia and Belarus at an aerodrome in Kaliningrad Region, Russia, September 13, 2021. REUTERS/Vitaly Nevar

Russian paratroopers wait before boarding Ilyushin Il-76 transport planes as they take part in the military exercises "Zapad-2021" staged by the armed forces of Russia and Belarus at an aerodrome in Kaliningrad Region, Russia, September 13, 2021. REUTERS/Vitaly Nevar

Russian paratroopers wait before boarding Ilyushin Il-76 transport planes as they take part in the military exercises "Zapad-2021" staged by the armed forces of Russia and Belarus at an aerodrome in Kaliningrad Region, Russia, September 13, 2021. REUTERS/Vitaly Nevar

Russian paratroopers walk before boarding Ilyushin Il-76 transport planes as they take part in the military exercises "Zapad-2021" staged by the armed forces of Russia and Belarus at an aerodrome in Kaliningrad Region, Russia, September 13, 2021. REUTERS/Vitaly Nevar

Canada's Prime Minister Justin Trudeau boards his campaign plane in Quebec Canada, September 12, 2021. REUTERS/Carlos Osorio

Pope Francis boards the plane for his visit to Hungary and Slovakia, at Fiumicino Airport near Rome, Italy, September 12, 2021. REUTERS/Alberto Lingria

Pope Francis boards the plane for his visit to Hungary and Slovakia, at Fiumicino Airport near Rome, Italy, September 12, 2021. REUTERS/Alberto Lingria

Pope Francis boards the plane for his visit to Hungary and Slovakia, at Fiumicino Airport near Rome, Italy, September 12, 2021. REUTERS/Alberto Lingria

Pope Francis arrives to board the plane for his visit to Hungary and Slovakia, at Fiumicino Airport near Rome, Italy, September 12, 2021. REUTERS/Alberto Lingria

The plane with Pope Francis on board is seen on the tarmac before departing for his visit to Hungary and Slovakia, at Fiumicino airport near Rome, Italy, September 12, 2021. REUTERS/Alberto Lingria

Pope Francis sits on the plane before departing for his visit to Hungary and Slovakia, at Fiumicino Airport near Rome, Italy, September 12, 2021. REUTERS/Alberto Lingria

Pope Francis boards the plane for his visit to Hungary and Slovakia, at Fiumicino Airport near Rome, Italy, September 12, 2021. REUTERS/Alberto Lingria

Pope Francis boards the plane for his visit to Hungary and Slovakia, at Fiumicino Airport near Rome, Italy, September 12, 2021. REUTERS/Alberto Lingria

Pope Francis arrives to board the plane for his visit to Hungary and Slovakia, at Fiumicino Airport near Rome, Italy, September 12, 2021. REUTERS/Alberto Lingria

Pope Francis boards the plane for his visit to Hungary and Slovakia, at Fiumicino Airport near Rome, Italy, September 12, 2021. REUTERS/Alberto Lingria

Pope Francis greets the crew as he boards the plane for his visit to Hungary and Slovakia, at Fiumicino Airport near Rome, Italy, September 12, 2021. REUTERS/Alberto Lingria

Pope Francis boards the plane for his visit to Hungary and Slovakia, at Fiumicino Airport near Rome, Italy, September 12, 2021. REUTERS/Alberto Lingria

Pope Francis boards the plane for his visit to Hungary and Slovakia, at Fiumicino Airport near Rome, Italy, September 12, 2021. REUTERS/Alberto Lingria

Pope Francis arrives to board the plane for his visit to Hungary and Slovakia, at Fiumicino Airport near Rome, Italy, September 12, 2021. REUTERS/Alberto Lingria

U.S. President Joe Biden and first lady Jill Biden depart after visiting the nearby site in Shanksville where the hijacked United Airlines Flight 93 plane crashed, on the 20th anniversary of the September 11, 2001 attacks, the Pennsylvania Army National Guard Base in Johnstown, Pennsylvania, U.S., September 11, 2021. REUTERS/Jonathan Ernst

U.S. first lady Jill Biden brings beer as she and President Joe Biden arrive to greet people at the Shanksville volunteer fire station, stopping at the fire hall after visiting the nearby site where the hijacked United Airlines Flight 93 plane crashed, on the 20th anniversary of the September 11, 2001 attacks, in Shanksville, Pennsylvania, U.S., September 11, 2021. Biden has repeatedly visited the firehouse over the years since 2001. REUTERS/Jonathan Ernst

U.S. President Joe Biden speaks to reporters before paying his respects at a 9/11 memorial outside the Shanksville volunteer fire station, as he and first lady Jill Biden stopped at the fire hall after visiting the nearby site where the hijacked United Airlines Flight 93 plane crashed, on the 20th anniversary of the September 11, 2001 attacks, in Shanksville, Pennsylvania, U.S., September 11, 2021. Biden has repeatedly visited the firehouse over the years since 2001. REUTERS/Jonathan Ernst

U.S. President Joe Biden pays his respects at a 9/11 memorial outside the Shanksville volunteer fire station, as he and first lady Jill Biden stopped at the fire hall after visiting the nearby site where the hijacked United Airlines Flight 93 plane crashed, on the 20th anniversary of the September 11, 2001 attacks, in Shanksville, Pennsylvania, U.S., September 11, 2021. Biden has repeatedly visited the firehouse over the years since 2001. REUTERS/Jonathan Ernst

U.S. President Joe Biden hugs a woman while visiting firefighters outside the Shanksville volunteer fire station, as he and first lady Jill Biden stopped at the fire hall after visiting the nearby site where the hijacked United Airlines Flight 93 plane crashed on the 20th anniversary of the September 11, 2001 attacks, in Shanksville, Pennsylvania, U.S., September 11, 2021. Biden has repeatedly visited the firehouse over the years since 2001. REUTERS/Jonathan Ernst

United Airlines flight attendants who fly the Flight 93 route watch and listen as U.S. President Joe Biden talks to reporters outside the Shanksville volunteer fire station, as he and first lady Jill Biden stopped at the fire hall after visiting the nearby site where the hijacked United Airlines Flight 93 plane crashed on the 20th anniversary of the September 11, 2001 attacks, in Shanksville, Pennsylvania, U.S., September 11, 2021. Biden has repeatedly visited the firehouse over the years since 2001. REUTERS/Jonathan Ernst

U.S. President Joe Biden greets firefighters outside the Shanksville volunteer fire station, as he and first lady Jill Biden stopped at the fire hall after visiting the nearby site where the hijacked United Airlines Flight 93 plane crashed on the 20th anniversary of the September 11, 2001 attacks, in Shanksville, Pennsylvania, U.S., September 11, 2021. Biden has repeatedly visited the firehouse over the years since 2001. REUTERS/Jonathan Ernst

U.S. President Joe Biden pays his respects at a 9/11 memorial outside the Shanksville volunteer fire station, as he and first lady Jill Biden stopped at the fire hall after visiting the nearby site where the hijacked United Airlines Flight 93 plane crashed, on the 20th anniversary of the September 11, 2001 attacks, in Shanksville, Pennsylvania, U.S., September 11, 2021. Biden has repeatedly visited the firehouse over the years since 2001. REUTERS/Jonathan Ernst

U.S. President Joe Biden pays his respects at a 9/11 memorial outside the Shanksville volunteer fire station, as he and first lady Jill Biden stopped at the fire hall after visiting the nearby site where the hijacked United Airlines Flight 93 plane crashed, on the 20th anniversary of the September 11, 2001 attacks, in Shanksville, Pennsylvania, U.S., September 11, 2021. Biden has repeatedly visited the firehouse over the years since 2001. REUTERS/Jonathan Ernst

U.S. President Joe Biden talks with reporters outside the Shanksville volunteer fire station, as he and first lady Jill Biden stopped at the fire hall after visiting the nearby site where the hijacked United Airlines Flight 93 plane crashed, on the 20th anniversary of the September 11, 2001 attacks, in Shanksville, Pennsylvania, U.S., September 11, 2021. Biden has repeatedly visited the firehouse over the years since 2001. REUTERS/Jonathan Ernst

U.S. President Joe Biden talks with reporters outside the Shanksville volunteer fire station, as he and first lady Jill Biden stopped at the fire hall, after visiting the nearby site where the hijacked United Airlines Flight 93 plane crashed, on the 20th anniversary of the September 11, 2001 attacks, in Shanksville, Pennsylvania, U.S., September 11, 2021. Biden has repeatedly visited the firehouse over the years since 2001. REUTERS/Jonathan Ernst

U.S. President Joe Biden talks with reporters outside the Shanksville volunteer fire station, as he and first lady Jill Biden stopped at the fire hall after visiting the nearby site where the hijacked United Airlines Flight 93 plane crashed on the 20th anniversary of the September 11, 2001 attacks, in Shanksville, Pennsylvania, U.S., September 11, 2021. Biden has repeatedly visited the firehouse over the years since 2001. REUTERS/Jonathan Ernst

Paramedic Christian Boyd, one of the first responders on 9/11, rings a bell of remembrance for each person who died on the hijacked United Airlines Flight 93 plane crash, during an event commemorating the 20th anniversary of the September 11, 2001 attacks at the Flight 93 National Memorial in Stoystown, Pennsylvania, U.S., September 11, 2021. REUTERS/Evelyn Hockstein

U.S. President Joe Biden talks with a woman while visiting firefighters outside the Shanksville volunteer fire station, as he and first lady Jill Biden stopped at the fire hall after visiting the nearby site where the hijacked United Airlines Flight 93 plane crashed on the 20th anniversary of the September 11, 2001 attacks, in Shanksville, Pennsylvania, U.S., September 11, 2021. Biden has repeatedly visited the firehouse over the years since 2001. REUTERS/Jonathan Ernst

U.S. President Joe Biden hugs a woman while visiting firefighters outside the Shanksville volunteer fire station, as he and first lady Jill Biden stopped at the fire hall after visiting the nearby site where the hijacked United Airlines Flight 93 plane crashed on the 20th anniversary of the September 11, 2001 attacks, in Shanksville, Pennsylvania, U.S., September 11, 2021. Biden has repeatedly visited the firehouse over the years since 2001. REUTERS/Jonathan Ernst

U.S. first lady Jill Biden hands out six packs of beers to firefighters outside the Shanksville volunteer fire station, as she and President Joe Biden stopped at the fire hall after visiting the nearby site where the hijacked United Airlines Flight 93 plane crashed on the 20th anniversary of the September 11, 2001 attacks, in Shanksville, Pennsylvania, U.S., September 11, 2021. Biden has repeatedly taken the firefighters at the station beers and food over the years since 2001. REUTERS/Jonathan Ernst

U.S. President Joe Biden and first lady Jill Biden greet firefighters outside the Shanksville volunteer fire station, as Biden stopped at the fire hall after visiting the nearby site where the hijacked United Airlines Flight 93 plane crashed on the 20th anniversary of the September 11, 2001 attacks, in Shanksville, Pennsylvania, U.S., September 11, 2021. REUTERS/Jonathan Ernst