Hopes that UK flights would soon return to normal have been undermined by a second volcanic ash cloud in Iceland.
Chances to operate planes at many UK airports have been short-lived, and only a few flights have taken place.
Airspace in most of the UK remains closed until at least 0100 BST on Wednesday, but curbs have been eased in some northern parts of the UK.
Airlines said the restrictions were an overreaction, but the government said safety was its absolute priority.
In its latest assessment of conditions, released at 1500 BST, air traffic control body Nats said part of Scottish and Northern Irish airspace including Aberdeen, Inverness and Edinburgh airports, will be available from 1900 BST on Tuesday to 0100 BST on Wednesday.
And Glasgow and Teesside airports will also become available for flights during this time.
On mainland Europe, some 14,000 flights are expected to take off on Tuesday – about half the normal number.
Nats has allowed for "overflights" – flights that pass over UK airspace at an altitude above 20,000 feet – allowing for many flights between Europe and the Middle East and North America.
But that is little consolation for many of the estimated 150,000 Britons that have been stranded overseas as a result of the flight restrictions.
Airlines have begun to question the level of restrictions to UK flights.
David Henderson, of the Association of European Airlines, told the BBC the lockdown on flights was an overreaction.
He said: "We believe that flying should be taking place."
But Transport Secretary Lord Adonis said the safety of air passengers remained the "paramount concern".
The minister, who said he had maintained a constant dialogue with European and UK regulators regarding flights, added: "All decisions being taken by the aviation regulators are intended solely to protect the travelling public, and I will not compromise passenger safety."
Meanwhile, British Airways has said 12 long-haul flights were currently en route to Heathrow, from Beijing, Singapore and the US west coast.
A spokeswoman said the airline had contingency plans for each flight if Heathrow was still closed but would not say which airports it would use instead.
It had been hoped that the intensity of volcanic eruptions was reducing, but the emergence of a new ash cloud has meant plans to reopen British airspace have been revised.
Jonathan Astill of Nats said the new ash cloud was a "significant change" to the situation on Monday.
He told BBC News: "The Met Office is reporting a further ash cloud that is coming down from Iceland and then covering the UK progressively during the day."
In a statement, Nats said: "The situation regarding the volcanic eruption in Iceland remains dynamic and the latest information from the Met Office shows that the situation will continue to be variable."
Schedules are constantly changing and passengers have been advised not to travel to airports until they have checked with their airline or tour operator.
The spread of volcanic ash has affected large swathes of Europe for the past five days.
There has been huge disruption for air travellers, many of whom have embarked on long and costly journeys over land and sea to get home.
Mr Astill of Nats said the government is maintaining increased capacity for passengers to cross the channel.
There are an extra 20,000 passenger places a day across Eurostar, Eurotunnel and the ferries, according to Lord Adonis.
In other developments:
Some UK banks arewaiving fees for money withdrawn by passengers stranded overseasby the ash cloud UK airports operatorBAA says the flight restrictions are costing it between £5m and £6m a dayService personnel and civilians boarded HMS Albion in the Spanish port of Santander and left for the UK at lunch time. Achange in wind direction by the weekend could help blow the volcanic ash cloud awayfrom Europe, according to a BBC meteorologist The Joint Council for Qualificationssays exams may be rescheduledfor students caught up in the travel chaos, while thepay of Devon teachers stranded for the same reasons may be dockedSporting fixturesaround Europe continue to be disrupted Nissan says it issuspending the manufacturing of three of its modelsbecause of supply chain problems
Anyone concerned about the safety of a British national stranded abroad can call a Foreign Office helpline on 020 7008 0000, or visit its
Stranded Britons should contact their local embassy, high commission or consulate.
This article is from the BBC News website. © British Broadcasting Corporation, The BBC is not responsible for the content of external internet sites.
- Snowfall delays Christmas getaway
- European summit on finance crisis
- Visa victory for language schools
- Audio slideshow
- Cineworld enjoys 3D film effects
Article Source: FendyBt2 Official Website
If you like all this stuff here then you can buy me a pack of cigarettes.