America is drawing up plans for a “bloody nose” military attack on North Korea to stop its nuclear weapons programme, The Telegraph understands.

The White House has “dramatically” stepped up preparation for a military solution in recent months amid fears diplomacy is not working, well-placed sources said.

One option is destroying a launch site before it is used by the regime for a new missile test. Stockpiles of weapons could also be targeted.

The hope is that military force would show Kim Jong-un that America is “serious” about stopping further nuclear development and trigger negotiations.

Three sources - two former US officials familiar with current thinking and a third figure in the administration - confirmed military options were being worked up.

“The Pentagon is trying to find options that would allow them to punch the North Koreans in the nose, get their attention and show that we’re serious", said one former US security official briefed on policy.