US president Donald Trump said on Tuesday that North Korea would be “met with fire and fury like the world has never seen”, escalating his rhetoric against the nuclear aspirant following fresh reports about its galloping missile programme.

“North Korea best not make any more threats to the United States,” Mr Trump told reporters, following details that the country has produced a miniaturised nuclear weapon that can be carried on its ballistic missiles. The intelligence reports, carried by The Washington Post, underline the grave threat that the Trump administration has spent the past seven months striving to stem.

The US is the only country that has used nuclear weapons in wartime before, when it detonated two nuclear bombs on Japan that it calculated would help bring the second world war to an end in 1945.