The UK Government was last night accused by the Conservatives of "panic" after it moved to free up £200m of defence spending to help secure two new aircraft carriers and provide equipment for front-line troops.

It emerged that the Treasury has agreed to allow the Ministry of Defence more flexibility in its budget to meet immediate priorities, including the politically sensitive issue of the aircraft carriers. However, the extra money is on condition the MoD carries out a major review of other projects. This has led to fears of increasing uncertainty in the defence industry.

The latest development comes just days after The Herald reported how the cost of the two new aircraft carriers has jumped by £300m to £4.2bn.

The UK Government is now expected to try to accelerate agreement of the long-delayed contract to ensure the escalating price tag does not lead to the project being scrapped.

The Treasury pegged the "maximum" cost of the warships at £3.9bn on January 1, 2007, but that figure takes no account of inflation and increases in the cost of labour and materials in the interim.

The carrier contract is designed to underpin 10,000 British shipbuilding jobs, including 3500 on the Clyde, until the middle to late years of the next decade and is regarded by Downing Street as sacrosanct in the run-up to the next General Election, expected in the spring or summer of 2010.

Yesterday, Liam Fox, the Shadow Defence Secretary, said the freeing-up of the £200m was "not driven by any rational examination of military equipment needs but by the gaping hole in the Treasury left by Gordon Brown's economic mismanagement".

He added: "Long-term planning has been abandoned in a panic attempt to plug the gaping hole in the defence budget. This effectively signals the end of the Defence Industrial Strategy and will add further uncertainty to the defence industry at a time when unemployment is already rising."

However, last night, a source close to Des Browne, the Defence Secretary, said: "These measures are about long-term planning. The Tories need to stop posturing and say exactly what they would do differently and whether or not they would match the government's spend on defence."

Earlier, an MoD spokeswoman said the department was determined to do more to support the military and that meant a better prioritisation of its spending plans.

"The examination of the equipment programme will focus on two issues above all: bearing down on cost increases to equipment programmes and rebalancing the equipment programme to better support the front line."

She added: "If the examination identifies savings, the Treasury has agreed to flexibility within the existing settlement to make those changes that will enable us to rebalance our plans. This will not be new money, merely flexibility within the settlement."