Warnings that a "new ash cloud" is spreading towards the UK as the volcano eruption in Iceland "strengthened" have left air passengers braced for further delays.
Air traffic control company Nats described the situation as "variable", but it said Scottish airports should be available from early on Tuesday and other airspace over England from 1pm, although not including the main London airports.
In an update shortly before 3am on Tuesday, Nats said: "Since our last statement the volcano eruption in Iceland has strengthened and a new ash cloud is spreading south and east towards the UK."
Based on this information, British Airways has cancelled all short-haul flights on Tuesday, but said it hoped to run long-haul flights scheduled to depart after 4pm, depending on a "full and permanent" opening of airspace.
BA said customers would be able to claim a full refund or rebook their trip for a later date if they had booked to travel on a cancelled flight.
Newcastle International Airport confirmed it planned to reopen for flights to and from Aberdeen and the Isle of Man early on Tuesday, adding that easyJet was hoping to operate a "very limited service" from late afternoon.
A spokeswoman for Newcastle International Airport said the first flight was expected to arrive at 9.20am from Aberdeen.
However, Manchester Airport said, due to the latest advice from Nats, it was not planning to open before 1pm.
A spokesman said: "It is absolutely essential that people contact their airline before travelling to the airport because even if Manchester Airport is able to reopen, schedules will take several days to return to normal."
© Press Association 2010