The US expressed “concern” over defence cuts in the UK and other European countries, as Britain’s defence chiefs demanded last-ditch talks with David Cameron in an attempt to avoid the Treasury’s axe.
With the defence negotiations in near deadlock over about £1bn of cuts, the heads of all three armed services met the prime minister in Downing Street on Thursday to raise the alarm over the dangers of such a tight settlement.
Their warnings were amplified by Hillary Clinton, US secretary of state, and Robert Gates, US defence secretary, who made public their worries over cuts across Nato.
Members of the organisation are asked to spend 2 per cent of national income on defence.
Asked whether the cuts in Britain and Europe worried her, Ms Clinton said: “It does ...because I think we do have to have an alliance where there is a commitment to the common defence.”
Mr Gates expressed his fear that the US would be called upon more often to cover Nato capability gaps. “As nations deal with their economic problems, we must guard against the hollowing out of alliance military capability by spending reductions that cut too far into muscle,” he said.
Mr Cameron’s team is acutely aware that defence is becoming the most fractious and politically difficult element of the spending review.
The prime minister is making a concerted attempt to show his “passion” for the forces, notably in a photocall on Thursday with Arnold Schwarzenegger, governor of California, and Grenadier Guards.
But he is facing an unpalatable list of defence review options, given the budget squeeze, a legacy of contractual overcommitments and uncompromising defence chiefs.
While the prime minister is pushing on with building two new aircraft carriers, a fierce debate is raging on how they should be used and what fighter jets should be retained. It is ever likelier that Mr Cameron will keep the land-based Tornado jets rather than the Harrier, a position supported by Sir Jock Stirrup, the outgoing chief of defence staff.
However, that will leave a capability gap of several years. The first carrier will have no aeroplanes to fly off it and will instead act as a platform for helicopters.
The navy is concerned that this will endanger the ability to regenerate a carrier strike capability once the Joint Strike Fighter comes into service towards the end of the decade.
As the Treasury presses for savings of up to 10 per cent, the army is also under pressure to reduce its manpower by 5,000 or more by 2015 and a further 15,000 before 2020.
A National Audit Office report will underscore the poor state of the Ministry of Defence budget on Friday, revealing that the equipment budget saw overruns of £3.3bn in the final year of Labour’s time in office.