The RAF is to lose a quarter of its frontline bomber force and two bases in new cuts to be pushed through by the Treasury, according to senior defence sources.

Two squadrons of Tornado GR4 ground attack aircraft will be scrapped, cutting the RAF’s frontline squadrons from eight to six. One helicopter base and one training base will also be closed, with the land sold off to raise cash.

The move comes as the Royal Navy is braced for big cuts to its surface fleet with all four Type22 frigates and a destroyer set to be axed “as soon as possible”. Other ships are under threat.

An internal e-mail leaked last month said that the “poor” deal for the Ministry of Defence (MoD) from the government’s Comprehensive Spending Review meant the loss of five ships by April.

Although the MoD has been promised a 1.5% increase in real terms in its budget over the next three years, the cost of future projects such as two new aircraft carriers is forcing it to make cuts elsewhere.

The sources said the MoD “equipment plan” for 2008 – which details all planned purchases – was rejected last month as too costly, largely as a result of urgently needed kit for troops in Iraq.

The cuts to the RAF come despite an insistence last month by Sir Glenn Torpy, chief of the air staff, that it was already “as lean as it can get”. In 2004 the RAF was forced to cut a quarter of its frontline squadrons, one base and 7,500 personnel.

“The idea of getting rid of two of the very few squadrons capable of providing our troops on the ground with close air support, just as the Tornado is set to go to Afghanistan, is a sign of how stupid these people are,” one senior source said.

The two Tornado GR4 squadrons to be scrapped are expected to be one each from the aircraft’s bases at RAF Marham in Norfolk and RAF Lossiemouth, Morayshire; 13 Squadron, based at Marham, is at present training over Scotland for a deployment to Afghanistan next year.

There are three Tornado GR4 squadrons at each base. A squadron has 12 aircraft with 15 crews and four aircraft held in reserve. The other two frontline ground attack aircraft squadrons are equipped with the ageing Harrier aircraft.

The two bases to be scrapped have not yet been named but it is believed that one of them is Odiham, Hampshire, home of the RAF’s Chinook fleet. It is seen as being the most vulnerable because its prime position within the extended London commuter belt would make its sale highly profitable.

The most likely training base closure would see the end of RAF Linton-on-Ouse in North Yorkshire, with all fast jet training amalgamated at RAF Valley in Anglesey. Linton-on-Ouse was a famous second world war bomber station once commanded by Arthur “Bomber” Harris, head of Bomber Command, and later Group Captain Leonard Cheshire VC, founder of the international charity bearing his name.

Moving its 78 Tucano training aircraft to Anglesey is likely to be unpopular because it will mean increased numbers of low-flying aircraft over Wales, which have always been a serious irritation for local farmers.

The cuts come despite a shortage of fast jet aircraft for operations and a need to limit the hours that each aircraft flies so that the Harrier fleet can stay operational until its replacement in 2017. A lack of long runways has seen the short take-off and landing Harrier providing close air support to British troops in Afghanistan.

John Nichol, the navigator of an RAF Tornado shot down over Iraq during the 1991 Gulf war, said the cuts left the RAF with “a disaster waiting to happen”.

“When we were flying over Iraq during the Gulf war we thought we were being stretched to the absolute limit,” he said. “The men and women flying now are working 100 times harder than we ever had to do. They are asked to do far more with far less.

“The military are their worst enemies. Their can-do attitude means they will always strive to do the job regardless of the resources the politicians give them. This isa disaster in the making, it really is.”

The cuts are not the RAF’s only problems. The government’s deal to sell 75 Typhoon aircraft to Saudi Arabia and the decision to use the new Typhoon aircraft in Afghanistan mean that some Tornado F3 fighters will have to stay in service for another eight years.

The F3 was due to be scrapped next year and replaced by the Typhoon – formerly known as the Eurofighter. But the controversial al-Salam deal with Riyadh will mean that there are insufficient aircraft to cover Britain’s air defences. Consequently, the F3 will stay in service till 2015.

An MoD spokesman said talk of cuts to the RAF and Royal Navy were part of an initial phase of discussions ahead of next year’s planning round and no firm decisions had been taken.

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