North Korea could develop missiles that can reach Europe sooner than expected, the French defence minister has warned.

Florence Parly told the French military in Toulon there are risks to the continent from intercontinental ballistic missiles being built by Kim Jong Un's regime.

Her comments came as President Trump and Theresa May held a call to discuss North Korea, during which the Prime Minister insisted it was "important for the international community to send out a clear message" to the reclusive state.

Meanwhile, Mr Trump said on Twitter he is allowing Japan and South Korea to buy "a substantially increased amount of highly sophisticated military equipment from the United States".

Image: The latest missile test in North Korea. Pic: Korean Central News Agency

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France's defence minister Ms Parly said in a speech: "The scenario of an escalation towards a major conflict cannot be discarded.

"Europe risks being within range of Kim Jong Un's missiles sooner than expected."

The North was reportedly seen moving what appeared to be an intercontinental ballistic missile towards its west coast.

South Korea's Asia Business Daily cited an intelligence source as saying the rocket was spotted moving on Monday, the day after Pyongyang's sixth and largest nuclear test.

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The North Korean missile programme's launch facilities are on its west coast - and the move was reportedly made during the night to avoid surveillance.

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South Korea's defence ministry could not confirm the report, but it said on Monday its neighbour was ready to launch more missiles.

In July, North Korea tested two ICBMs capable of flying about 6,200 miles, threatening parts of the US mainland.

The closest European country to North Korea is Norway, which is a straight-line distance of around 3,900 miles away.

Ms Parly's warning comes days after North Korea claimed to have carried out a hydrogen bomb test - estimated by South Korea to have been three times as powerful as the Hiroshima atomic bomb.

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Foreign Secretary Boris Johnson described the test as "another perilous advance in North Korea's nuclear ambitions", adding that China should "use all of its leverage to ensure a peaceful settlement of this grave crisis".

"Kim Jong Un claims to want security and prosperity for North Korea's people," he told the Commons.

"The only way to achieve this goal would be for North Korea to obey the UN and halt its nuclear weapons and ballistic missile programmes, disarming in a complete and verifiable manner."

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Earlier, one of North Korea's top diplomats said his country was ready to send "more gift packages" to the United States.

Image: Kim Jong Un inspecting a device which North Korea claimed was an H-bomb

Han Tae Song, North Korea's ambassador to the UN, told a conference on disarmament: "The recent self-defence measures by my country...are a 'gift package' addressed to none other than the US.

"The US will receive more 'gift packages' from my country as long as it relies on reckless provocations and futile attempts to put pressure on the DPRK."

South Korea's UN representative, Kim Inchul, accused Pyongyang of "delusion" over its nuclear programme.

He told the conference: "Under that delusion they dare to make the preposterous advice, which is inadmissible in the conference of disarmament, that it is OK to pursue a nuclear programme."