The government has said it will be "more open" about the UK's nuclear weapons capability after announcing it will retain a maximum of 225 warheads.

It was revealed in 2006 the UK had 160 "operationally available" warheads but the extra numbers needed above this to allow for maintenance were not stated.

Foreign Secretary William Hague said the disclosure would help build trust between nuclear and non-nuclear states.

The US and France have already released details of their total warhead numbers.