STRANDED Britons across the world saw some light ahead as UK airspace began to reopen from 10pm last night.
Civil Aviation Authority (CAA) chairwoman Dame Deirdre Hutton said none of the no-fly zones caused by the volcanic ash cloud were currently over Britain.
Transport Secretary Lord Adonis said all British airports could reopen and he expected them to remain open.
Many airports had already cancelled flights, however.
Cardiff Airport is expected to decided this morning on when to resume flights. A spokeswoman said last night everyone scheduled on flights must contact their airlines before travelling.
A spokesman for BAA, which operates Heathrow, said it would do everything possible to “get people moving”.
“We are ready to open, but until further notice passengers must contact their airline before travelling to the airport,” the spokesman said.
“Not all flights will operate during the early period of opening, and we will do everything we can to support airlines and get people moving.”
The news was cautiously welcomed.
On Monday night, UK airspace was widely expected to open yesterday morning until a late update at 10pm showed worsening eruptions from the Icelandic volcano Eyiafjallajokull, which again shut down the air lanes.
There were a handful of flights in parts of Scotland, Northern Ireland and north-east England yesterday but air traffic control company Nats had earlier said the restriction on flights in the rest of England and Wales would remain until at least 1am today.
The CAA said last night it was a “situation without precedent” and that decisions had been made based on “thorough gathering of data and analysis”.
“The major barrier to resuming flight has been understanding tolerance levels of aircraft to ash,” the CAA said.
“Manufacturers have now agreed increased tolerance levels in low ash density areas.”
Lord Adonis said safety was the “paramount concern” but research into the effects of the volcanic ash had led to a “better” understanding of the implications.
Willie Walsh, chief executive of British Airways, welcomed the lifting of the restrictions.
He said: “Safety has been at the forefront of everybody’s minds while reaching this decision.
“We are now going to start the difficult task of getting our stranded customers home.”
Earlier, BA said more than 20 long-haul flights were headed towards the UK, at a time when restrictions were still in place.
But Mr Walsh, stressed safety was never compromised.
“There was no concern from a safety point of view,” he said.
The row over the grounding of planes intensified yesterday, with London Mayor Boris Johnson, former Ukip leader Nigel Farage, travel company Thomas Cook and Mr Walsh expressing concerns about the grounding of flights.
Mr Walsh said: “I don’t believe it was necessary to impose a blanket ban on all UK airspace last Thursday.
“My personal belief is that we could have safely continued operating for a period of time.”
Meanwhile, the struggle to bring home the estimated 150,000 Britons stranded abroad continued.
Royal Navy vessel HMS Albion sailed to Santander, in northern Spain, to pick up around 280 stuck holidaymakers as well as around 450 troops.
The new £500m Celebrity Cruises ship Celebrity Eclipse, was due to leave Southampton last night to pick up stranded Britons in Bilbao, northern Spain.
Some airlines and tour operators arranged special flights to at least get stricken Britons back to mainland Europe, while there were an extra 20,000 passenger places a day across Eurostar, Eurotunnel and the Channel ferries.
But the Foreign Office warned: “Given the likely numbers involved, it will take a matter of weeks before everyone can be repatriated.”
A spokeswoman for Nats said last night: “Nats will review airspace availability and provide an update to airline operators on any airspace that has been restricted for safety reasons.”