The defence secretary has set out plans for a "transformation" of Britain's armed forces.

Geoff Hoon told MPs on Wednesday that the government was committed to defending Britain.

But he said that to face the complexities of the post-Cold War world and the threat of global terrorism, the armed forces would focus more on new technologies and less on troop numbers.

Controversially, four infantry battalions are to be axed, three from England and one from Scotland, as the armed forces are "restructured".

The Royal Navy will lose three type-42 destroyers and three type-23 frigates by March 2006.

And one RAF Tornado F-3 air defence squadron would be cut, while the withdrawal of two Jaguar squadrons would be brought forward to 2006. The final Jaguar squadron to be disbanded in 2007.

RAF manpower will reduce from 48,500 to around 41,000 by April 2008, with RAF Coltishall in Norfolk to be closed by the end of 2006.

Navy manpower will be reduced from 37,500 to around 36,000 by April 2008,

And once "full normalisation in Northern Ireland is achieved" the Ministry of Defence said it would expect to see an army of around 102,000 troops.

With a target of £2.8 billion in efficiency savings, civilian MoD numbers will reduce by more than 10,000 by April 2008.

"The majority of reductions will effect not the front lines but support operations," Hoon said.

He pledged that "the capability of our armed forces is growing year by year".

But the Conservatives slammed the plans, warning they would "seriously damage our military capability".

Shadow defence secretary Nicholas Soames said "this announcement is essentially about cuts".

"Most of the current difficulties in defence are entirely of this government's own making," he said.

Warning of a "deep crisis" in the defence budget, Soames said the government's defence plans were "never properly costed nor properly funded".

And he said it was "reckless" to make cuts now to fund new weapons that would be delivered "in the dim and distant future".