South Korea's new leader says he is willing to visit the North amid heightened tensions over Pyongyang's nuclear ambitions.

Left-leaning Moon Jae-in, who was sworn in as president in the capital Seoul, backs engaging diplomatically with the North.

But he faces a difficult task as Pyongyang aims to produce a missile capable of carrying a nuclear warhead that can attack the continental US.

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The North also has vast artillery forces that could target its southern rival.


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Mr Moon, 64, said: "I will urgently try to solve the security crisis. If needed, I will fly straight to Washington.

"I will go to Beijing and Tokyo and, if the conditions are right, to Pyongyang also."

His comments are in contrast to recent tough talk from the Trump administration, which has not ruled out military action against the North.

And it comes as the North's ambassador to the UK told Sky News his country will go ahead with its sixth nuclear test at the time and place of its leader Kim Jong Un's choosing.

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The South is also embroiled in a dispute with China over a controversial US missile defence system, which Beijing sees as a threat.

Mr Moon and the US President agreed "on close cooperation" to deal with the North's nuclear programme in a telephone conversation on Wednesday.

Mr Trump invited Democratic party leader Mr Moon to visit the US "as early as possible".

Meanwhile, Chinese President Xi Jinping congratulated Mr Moon on his election, saying he would be willing to work with him on a basis of "mutual understanding and mutual respect".

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At home, Mr Moon will have to deal with slowing growth, soaring unemployment and public frustration over widening gaps in wealth and opportunities.

He was elected following a corruption scandal that saw his conservative predecessor Park Geun-Hye impeached.

Ms Park's Liberty Korea party has accused him of being a Pyongyang sympathiser and he has reportedly "begged" for its co-operation.

He won 41.1% of the vote in Tuesday's election, ahead of Hong Joon-Pyo of the Liberty Korea party, on 24%, and centrist Ahn Cheol-Soo on 21.4%.