Below is a list of flight restrictions in European airports as of 16.00 today. All times are GMT.
AUSTRIA: Airspace expected to remain closed until at least midnight
BELGIUM: Airspace closed until at least 18.00. Main airline, Brussels Airlines, has cancelled all flights until tomrrow
BRITAIN: Airspace closed until at least 6.00 tomorrow. Update expected around 20.00. British Airways cancels all flights tomorrow
BULGARIA: Sofia and Plovdiv airports open as of 11.00. Other airports closed. Transit flights permitted at 8,000 metres altitude.
CZECH REPUBLIC: Airspace closed until at least 10.00 tomorrow
DENMARK: Airspace closed. Update due around 19.00
ESTONIA: Airspace closed until tomorrow
FINLAND: Airspace closed until at least 15.00 tomorrow
FRANCE: Bordeaux, Marseille, Nice, Toulouse and several other southwest airports will open until at least 13.00 tomorrow. Airports north of Nice-Bordeaux line remain closed at least until Tuesday morning. Air France said a test flight from Paris to Toulouse today ended without problems
GERMANY: Several airports open for flights heading in an easterly or northerly direction until 18.00
HUNGARY: Airspace to remain closed until at least 10.00 tomorrow, although some flights at the discretion of traffic control may be allowed to take off or land.
IRELAND: Airspace closed until at least 12.00 tomorrow. Ryanair has cancelled all flights to and from northern Europe until Wednesday afternoon. Aer Lingus has cancelled all flights tomorrow
ITALY: Northern airspace closed until at least 06.00 tomorrow
LATVIA: Airspace expected to stay closed until tomorrow
LITHUANIA: Airspace closed indefinitely according to Vilnius airport
LUXEMBOURG: Luxembourg airport closed until at least 16.00
NORWAY: Airspace opened for some traffic north of Bergen, with some northern areas still closed. Other main airports in southern Norway, such as Oslo Gardermoen and Stavanger, are still closed. Civil aviation authority Avinor said airspace over southern Norway as well as the few northern areas closed may open later today. Update expected around 19.00
NETHERLANDS: Dutch airline KLM cancels all European flights today and intercontinental flights from Amsterdam until at least 18.00. Airspace closed until at least 18.00 today.
POLAND: Six Polish airports, including Warsaw, reopen for commercial flights.
ROMANIA: Airspace closed until at least 09.00 tomorrow
RUSSIA: All airports open. Aeroflot is flying to the United States via the North Pole
SLOVAKIA: Airspace closed as of 13.00 on Friday
SPAIN: The 17 airports closed this morning by the Spanish airport authorities are now all open.
SWEDEN: Airspace closed all Sunday and tomorrow. Scandinavian Airlines said most of its flights on April 18th and 19th have been cancelled. A corridor of airspace in northern Sweden is open around Kiruna as is as a corridor to the Norwegian Sea.
SWITZERLAND: Airspace closed until at least 12.00 tomorrow
UKRAINE: Kiev's Borispol airport open
Reuters