'North Korea ready to react to 'any mode of war' from US'

North Korea is preparing for "any mode of war" triggered by US military action, Pyongyang's envoy to the United Nations warned today, saying his country would respond to a missile or nuclear strike "in kind."

The statement from North Korean Deputy Ambassador Kim In Ryong followed warnings from US Vice President Mike Pence to Pyongyang not to test US resolve following another missile test.

"If the United States dares opt for a military action (...) the DPRK is ready to react to any mode of war desired by the Americans," Kim told a news conference.

"We will take the toughest counteraction against the provocateurs," said Kim.

North Korea has taken "self-defensive" measures in response to US threats of military action and these reflect Pyongyang's determination to "counter nukes and ICBM in kind," he said, referring to intercontinental ballistic missiles.

Pence told a news conference in South Korea that "the era of strategic patience is over" after North Korea yesterday test-fired another missile as fears mounted that it may be preparing a sixth nuclear test.

Pyongyang is seeking to develop a long-range missile capable of hitting the US mainland with a nuclear warhead, and has so far staged five nuclear tests, two of them last year.

US President Donald Trump's decision at the weekend to send the Carl Vinson carrier-led navy strike group to the Korean peninsula shows that the "US reckless moves for invading the DPRK have reached a serious phase," said Kim.

The North Korean deputy envoy asserted that Pyongyang would hold the United States "wholly accountable for the catastrophic consequences to be entailed by its outrageous actions."

US Secretary of State Rex Tillerson will next week chair a special meeting of the UN Security Council on North Korea.