Airlines in Europe face a race to adapt their flight plans.
That after a Ryanair jet was forced to land in Belarus, sparking outrage in countries around the world.
A dissident Belarusian journalist travelling on the plane was seized by local authorities.
For the main airline of Belarus the consequences are simple enough.
Belavia has cancelled all flights to London and Paris after air permits were suspended by the UK and France.
The EU will also shut out the Belarusian carrier, with leaders calling for planes from the country to be banned from the bloc's airspace.
Other airlines operating in the region face more complicated decisions.
Lufthansa, Air France, KLM and SAS are among those to say they will avoid Belarus airspace.
But that's no easy task, as the country lies along a major air corridor connecting Europe and Asia.
European air traffic agency Eurocontrol says around 100 flights by EU and UK carriers normally fly over Belarus each day.
It's now advising them to route planes over the Baltic instead.
Ukraine will also ban flights to and from Belarus.
For air passengers the various route changes may mean journeys take longer.
For Belarus the consequences could be worse.
It could soon be reachable by air only over its border with close ally Russia.
And it stands to lose millions of dollars in fees payed by airlines to allow overflights.