The 'optional' plans for two extra Type-45 destroyers, in addition to the six already guaranteed, were set out by the government in 2001

But today in the House of Commons Armed Forces Minister Bob Ainsworth admitted the seventh and eighth ships would never be built.

The move means the Royal Navy will now have just half the number of Type-45 destroyers that was originally booted.

Mr Ainsworth told MPs there were not 'unlimited resources' for Naval spending, and insisted the six now on order had 'formidable capability'.

He said: 'We have to prioritise between a range of competing requirements, focusing on the balance between current operations and future capability.

'That is why I can confirm that we have taken a decision not to take the option to order the seventh and eighth Type 45 destroyers.'

VT which has been building the bow sections for the destroyers, said it was not surprised by the move.