LONDON — A North Korean envoy says his country has developed nuclear missiles and is prepared to use them at any time.

North Korean Ambassador to Britain Hyun Hak Bong said in an interview with British broadcaster Sky News that his government would use the missiles in response to a nuclear attack by the United States.

Asked whether North Korea has the ability now to fire a nuclear missile, Hyun replied, “Any time. Any time. Yes.”

“If the United States strike us, we should strike back,” he said.

North Korea is thought to have a handful of crude nuclear bombs and has conducted three nuclear tests since 2006. But experts are divided on how far it has come in the technology needed to miniaturize warheads so they can be placed on missiles.