EU leaders have urged all airlines based in the bloc to avoid flying over Belarus and moved to ban Belarusian planes from European skies.
Britain, which is no longer a member of the EU, also instructed airlines to avoid the country’s airspace to ensure passenger safety.
The moves came after Belarus scrambled a fighter jet to divert a Ryanair flight flying from Greece to Lithuania.
Opposition journalist Roman Protasevich and his girlfriend were arrested when the plane touched down in Minsk.
What are the EU air restrictions?
In a swift response to Sunday’s incident, the EU’s 27 leaders on Monday called for airlines based in the bloc to stop flying in Belarusian airspace.
They said they would ban Belarusian airlines from entering EU airspace, although this needs to be authorised by the European Council.
German Economy Minister Peter Altmaier said the response from the EU would “have very noticeable consequences”.
“Not only for the airlines but also for the country. This is the first step,” he said.
Separately, UK Transport Secretary Grant Shapps suspended the operating permit of Belarusian flag carrier Belavia, and instructed British airlines to avoid flying over Belarus.
How will the guidance affect air travel?
Belarus lies on a major corridor connecting Europe and Asia. Airlines would need to divert around the country, adding to journey time and increasing operating costs.
Aviation consultant John Strickland said although air travel was currently limited owing to the pandemic, some short-haul and long-haul flights could be affected by the move.
Mr Strickland said some routes may experience "longer journey time, with consequently extra fuel burn and equally disruptive schedules".
"A number of flights south to and from Lithuania would be affected, as would some flights from the Baltic states," he told The National.
"Some long-haul flights between Europe, the Middle East and Asia might be affected as well, though the flight path of these routes can vary day-to-day."
He added that it made no sense for the Ryanair flight to be diverted to Minsk when it was not the closest airport.
"I can’t think of anything like it. For a pilot to be given false information and escorted by the military is metaphorically like a gun to the head to divert," he said.
Russia criticised Europe’s plans to cut air links with Belarus, which was part of the former Soviet Union.
"We can only express regret. It is very expensive for any company to fly around the territory of a rather large country located in the centre of Europe," Kremlin spokesman Dmitry Peskov said.
"In the end, these recommendations will cost the passengers of the planes, who will be in the air for an extra half-hour or hour.”
What is the response from airlines?
Lufthansa, KLM, SAS, Air France, LOT and Singapore Airlines were among the major airlines to announce they would stop flying over Belarus.
British Airways appeared to be avoiding the airspace. A BA flight that was due to approach transit in Belarus diverted to Lithuania only an hour after Mr Shapps's announcement.
President of the European Council Charles Michel – who criticised Belarus for playing “Russian roulette” with people’s lives – tweeted a photo of empty airspace over the country.
“Europe in action,” he said.
Analysis of Flightradar24 data suggests Belarusian airspace is still being used by Russian airlines and cargo flights.
What is the reaction from Belarus?
Belarus said on Tuesday it had invited international aviation officials to investigate the forced landing of the commercial flight in Minsk carrying a dissident journalist.
The authorities said the flight was diverted because of a bomb threat from Palestinian militant group Hamas.
A senior transport official read a letter to reporters that he claimed was from the organisation.
"If you do not fulfil our demands, the bomb will explode over Vilnius," it said.
Hamas denied any involvement, while German Chancellor Angela Merkel said the Belarusian claim was "completely implausible".