The head of Britain's armed forces has revealed plans to prepare the UK for war amid a dire warning that the country is "really quite close to the threat of an armed conflict". Air Chief Marshal Sir Richard Knighton told Sky News an updated version of the Government War Book is being prepared.

The broadcaster reported on Friday that the plan would draw on lessons from the Cold War, but "in a modern context, with a modern society, with modern infrastructure". Meanwhile, Dr Rob Johnson, Director of the Changing Character of Conflict Centre at Oxford University, warned the world is "really quite close" to the threat of armed conflict.

A majority of indicators of conflict preparation and armed attack on a dashboard devised by the expert are flashing, according to the broadcaster.

Dr Johnson said: "We're about 94%, 95% complete. In other words, we're really quite close to the threat of an armed conflict."

Air Chief Marshal Sir Richard Knighton said he thought it was right when asked if the Government War Book was being revised.

The top secret war book was first developed during World War I. It was maintained throughout the Cold War and detailed how the UK would mobilise society in a crisis, from deploying armed forces to the rationing of supplies.

It was phased out in the early 2000s after the Soviet Union collapsed in December 1991.