Peace activists cursed "an historic opportunity missed" yesterday after Liberal Democrats backed their leaders' "Trident-lite" nuclear weapons programme.

The ageing nuclear submarines are due for a £65 billion overhaul by 2016, which anti-war and anti-austerity movements warn could top £120bn over the fleet's lifetime.

But the Lib Dem leadership have insisted that Britain should keep the fleet, but drop continuous at-sea patrols and cut the number of subs from four to two.