FLIGHTS will finally start again in the UK tomorrow after air traffic control company Nats lifted restrictions for Scotland and part of northern England.
After days without any flights above the UK due to volcanic ash, Nats said tonight that Scottish airspace would open at 7am tomorrow.
Airspace south to a line between Teesside and Blackpool will also be open, with the hope that restrictions over the rest of England and Wales will be lifted later tomorrow, Nats said.
But current restrictions for the UK would carry on until 7am tomorrow.
Nats said: "The volcanic eruption has reduced and the volcano is not currently emitting ash to altitudes that will affect the UK. Assuming there are no further significant ash emissions, we are now looking at a continuously improving situation.
"This is a dynamic and changing situation and is therefore difficult to forecast beyond 7am tomorrow.
"However, the latest Met Office advice is that the contaminated area will continue to move south, with the possibility that restrictions to airspace above England and Wales, including the London area, may be lifted later tomorrow.
"It is now for airports and airlines to decide how best to utilise this opportunity. Passengers should contact their airlines to find out how this will affect their travel plans."
The news will come as an enormous relief to cash-strapped airlines and the estimated 150,000 Britons stranded abroad by the flights ban.
Before the Nats announcement, Prime Minister Gordon Brown said that two Royal Navy ships were to be used to help bring Britons home, with a third vessel also possibly being deployed.
The go-ahead for flights came as airlines pointed to successful test flights through closed airspace as a reason for lifting restrictions.
Airline Flybe said it would start operating services again from Aberdeen, Belfast City, Edinburgh, Glasgow, Inverness and Newcastle airports from 10.05am tomorrow.
The first flight will take off from Belfast City airport at 10.05 heading for Edinburgh.
The lessening of the impact of the volcano and the promise of a change in wind direction by the end of the week holds out the hope that the crisis can soon be resolved.
The cost to airlines and other affected industries is immense and British Airways said today that European carriers had asked the EU and national governments for financial compensation.
BA, which took a test flight through a successful run out across the Atlantic yesterday, said the flight restrictions had cost it between £15 million and £20 million a day.
While Mr Brown and Transport Secretary Lord Adonis outlined measures to get Britons home, holiday companies Thomson and First Choice said they were laying on coaches to repatriate around 5,000 stranded tourists in the Spanish resorts of Alicante and Malaga.
Thomas Cook also announced that it was flying holidaymakers from the Caribbean to Portugal and getting them home from there.
Mr Brown said HMS Ark Royal and HMS Ocean would be used to help stranded Britons. A third vessel, HMS Albion, which was on its way to Spain to pick up troops, "may be able to be of help", the Prime Minister said.
The International Air Transport Association was highly critical of the European response to the ash crisis which, it estimated, is costing the aviation industry around 200 million dollars (£130 million) a day.
Meanwhile, ferry companies and train operators have been enjoying a travel boom in the absence of any UK plane travel.
Channel Tunnel high-speed train company Eurostar said it was putting on extra trains every day this week.
A spokeswoman for Newcastle International Airport said: ``At this stage it is uncertain what flights in and out of Newcastle will be possible and, assuming the airspace remains open, the normal flying programme will not be restored immediately.
"We will provide further details of the flights when they become available. Our advice for passengers with flights from Newcastle is still to contact their airline or to check our website for flight information."
The announcement of the possible naval deployment followed a meeting in London of Cobra, the Government's emergency contingency committee.
A Ministry of Defence spokesman said: "Following this morning’s Cobra meeting and the Prime Minister’s statement, we are looking at how a number of Royal Navy (RN) vessels could provide support to UK Government efforts to assist British travellers stranded abroad and wishing to return home to the UK.
"We are urgently looking into the detail of how this support will work in practice but as part of the preparations we are looking at how the RN will be employed to provide assistance to the Government’s wider efforts."
He went on: "HMS Albion is expected to arrive in Santander tomorrow morning where its primary role will be to collect UK service personnel who have recently left the ongoing operation in Afghanistan.
"HMS Ocean is currently in southern British waters and is standing by for tasking. HMS Ark Royal, who was deployed on exercise off the north-west coast of Scotland, is sailing south to provide further assistance as required.
"We are supporting detailed cross-government planning to confirm how best we can assist."
Christopher Snelling, head of global supply chain policy at the Freight Transport Association, said the flight ban had meant certain fresh produce, such as exotic fruits and fresh flowers, had become noticeable by their absence from supermarket shelves.
He said even with airspace opened again it would take two weeks to clear the backlog of air freight destined for the UK.
Ryanair chief executive Michael O’Leary, whose budget airline has axed all flights until 1pm on Wednesday, said he hoped to get flights going again "by lunchtime Wednesday".
He told Sky News he hoped to clear the backlog of flights "within a day or two".
Mr O’Leary said he had supported the decision to restrict flights but added that airlines need to have better information about what might happen if the volcanic activity worsened again.
Thomas Cook Group said the flight shutdown had cost it around £7 million a day.
Corporate travel services company Hogg Robinson estimated that a total of 63,000 flights had been cancelled.
A spokesman for Glasgow airport said: ``We strongly advise passengers to check the status of their flight before travelling to the airport, as not all flights will operate.
"All Scottish airports are currently working with airlines to understand their intentions in terms of operating flights.
"The ash cloud remains in the air over Europe, so this situation is dynamic and remains subject to change."
A Heathrow airport spokesman said: "The decision to lift airspace restrictions will be taken by others and, as things stand, all flights remain suspended.
"When airports do open for business, we will continue to strongly advise passengers that they must check the status of their flight with airlines before travelling to airports. We appreciate the continued patience of our passengers at this difficult time."
A spokesman for Gatwick airport said: "When the restrictions are lifted, our focus will be to get airlines and passengers back in the air. However, a return to normal operations could take some time.
"It is absolutely critical that people do not travel to the airport unless their flight has been confirmed. Speculative trips to the airport will only cause major congestion. Passengers should contact their airline to confirm when their flights have been rebooked."
A spokesman for Manchester Airport said: "Nats has confirmed that UK airspace will progressively open tomorrow.
"Consequently, Manchester Airport will be open from 9pm on Tuesday April 20, unless there is a deterioration in conditions.
"It is absolutely essential that people contact their airline before travelling to the airport for any flight because schedules will take some time to return to normal.
"After five days without flights, tens of thousands of passengers waiting to be repatriated and the ash cloud continuing to cover parts of Europe, significant disruption is likely before normal operations are resumed.
"We would like to thank passengers for their continued patience and understanding since this situation began on Thursday April 15."