Mr Rifkind took his battle with the Treasury over public spending on to the floor of the Commons with a declaration that 'arbitrary cuts would not be a sound or responsible way of conducting defence policy'.
In what will be read as a thinly veiled message to Kenneth Clarke, the Chancellor, Mr Rifkind used his speech opening a two-day defence debate to say that 'we have at present the right balance of forces' to carry out the military tasks agreed by the Government. Mr Rifkind said that current plans envisaged armed forces of some 240,000, while civil servants will fall to 135,000 or lower.
As expected, he announced that Britain would be making savings in the long term by cancelling plans for the pounds 3bn Tactical Air to Surface Missile, in favour of the much lower cost alternative of fitting sub-strategic warheads to the Trident system. But that decision will not affect the current bitterly fought spending round.
Mr Rifkind's pointed remarks, in a speech interrupted by a series of complaints from senior backbenchers about 'fatuous' and 'fatal' Treasury plans for further cuts of up to pounds 1bn, came after two reports from the Commons Defence Select Committee warning that any further reductions would undermine Britain's ability to defend itself.
Mr Rifkind had earlier put his case at an inconclusive meeting of senior ministers at Downing Street. A series of further meetings are expected over the next few days.
Mr Rifkind told the Commons that those responsible had a duty to the 'men and women who serve' and must ensure 'that they are only required to perform tasks for which they have sufficient manpower, good modern equipment and a clear and realistic statement of their aims'.
He added that 'fundamental to our confidence' in the three armed services 'is that we know that we have the resources to enable them to carry out those tasks expected of them'.
Answering an intervention by Cyril Townsend, Tory MP for Bexleyheath, who is opposed to further cuts, Mr Rifkind said that 'any deliberation of future policy has to look very responsibly and very comprehensively at both the commitments that the armed forces have and the way we can carry out those commitments'.
His task of mobilising support from Cabinet colleagues could be hampered by the fact that they too are battling to stave off cuts in their own budgets. But Douglas Hurd, the Foreign Secretary, while fighting his own corner, is known to be supportive of Mr Rifkind's contention that the answers to fundamental questions about Britain's international role should not simply be dictated by the Treasury's need to reduce the budget deficit in the short term.
On Channel 4 News last night Mr Rifkind made it clear he was not opposing administrative economies, for example through market testing. He said that operational commitments were currently 'in balance' with resources, but any cuts in capability would take the Government into 'the area of examining whether commitments will be reduced'.
Mr Rifkind also announced yesterday that the Rosyth and Devonport dockyards would be sold as separate and competing commercial entities, which would make possible 'further benefits for the Navy, the taxpayer and the yards themselves'.
And, in line with the Prime Minister's desire to end class distinctions in honours, he announced a new system of gallantry medals, including a new cross at the level immediately below the Victoria Cross, common to all ranks.
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