Liberal Democrats leader Sir Ed Davey is calling on the government to start building a “fully independent British nuclear deterrent” to end the UK’s reliance on the US.

The UK has operational control of its nuclear arsenal, including British-built warheads, but it depends on the US to supply and maintain the Trident missiles that would deliver them.

In a speech to his party’s spring conference in York on Sunday, Sir Ed will argue the UK’s continued reliance on US support is an unacceptable risk to national security.