North Korea calls Trump a 'lunatic old man' who may 'start nuclear war' as US and Japan hold summit

Regime state media responds to Trump's refusal to rule out military action against Pyongyang

Kim Jong-un and Trump have exchanged threats in recent months (Reuters/KCNA)

North Korean and US leaders have fired another round of harsh words, with the North Korean regime calling Donald Trump a “lunatic old man” seeking to start a nuclear war.

The regime state media accused Mr Trump of escalating tensions between the two countries “to the extremes”, adding that “no-one can predict when the lunatic old man of the White House, lost to sense, will start a nuclear war”.

The comments come as Mr Trump met with Japanese Prime Minister Shinzo Abe at a summit in Tokyo during his first tour of Asia as President, and both leaders refused to rule out military action against the neighbouring country.

“Some people say my rhetoric is very strong but look what has happened with very weak rhetoric in the last 25 years,” said the President.

While Mr Trump called the nation “a threat to the civilised world” – as he stood in range of a North Korean ballistic missile – Mr Abe agreed that, when it came to dealing with Kim Jong-un, “all options were on the table”. He also announced new sanctions against dozens of North Koreans.

Japan does not have a standing army as part of its post-war pacifist constitution, but it has so-called "self-defence forces".

Mr Abe is seeking to reverse this stance, given North Korea’s firing of missiles over the country twice in recent months. In September, North Korea also claimed it had tested a powerful hydrogen bomb.

Pyongyang has already declared Mr Trump as “deranged” in response to the President’s fiery speech at the United Nations summit in New York earlier this year.

Mr Trump called the regime leader “little rocket man” and vowed to meet any aggression with “fire and fury”, saying he would “totally destroy” the nation.

In recent months the US has also upped joint military drills with South Korea, including sailing fleets of warships and flying planes near the border, as well as practising dropping bombs on targets in South Korea.

Mr Trump tweeted in September that he was "allowing Japan and South Korea to buy a substantially increased amount of highly sophisticated military equipment from the United States."

He reiterated his vow during his stay in Japan this week, insisting that Japan would be able to shoot North Korean missiles "out of the sky" with such military equipment from the US.

Agencies contributed to this report.