North Korea has promised to use the toughest of counter-measures against what it called the invasion of Pyongyang and warned of “catastrophic consequences” as the US deployed a navy strike group to the Korean peninsula.

“We will hold the US wholly accountable for the catastrophic consequences to be entailed by its outrageous actions,” a spokesman for the North Korean foreign ministry said, quoted by the Korean Central News Agency (KCNA).

The strike group comprised of nuclear-powered aircraft carrier USS Carl Vinson and other warships has been diverted from Singapore to waters off the peninsula as tensions continue to rise in the region over North Korea’s nuclear provocations and missile tests.

“The prevailing grave situation proves once again that [North Korea] was entirely just when it increased in every way its military capabilities for self-defence and pre-emptive attack with a nuclear force as a pivot,” the spokesman said.

There is strong speculation that Kim Jong-un’s government is planning to conduct its sixth nuclear test or launch a long-range missile to coincide with a number of key anniversaries in April.

As it has repeatedly claimed before, North Korea said Washington’s military threats justified its development of nuclear and missile programmes.

The main newspaper in North Korea, Rodong Sinmun, warned that the country was capable of carrying out a pre-emptive attack against the US.

“We are ready to counter any type of an aggression war. It will be desirable for [the US] to ditch its plan of pre-emptive strikes [against us] to a trash can,” the newspaper said in a commentary, quoted by the Yonhap news agency in the South.

Equally, there are concerns that the US might carry out a pre-emptive strike against North Korea.

Acting alone

However, the South Korean defence ministry insisted on Tuesday that any substantive military action against North Korea would take place only with “close co-operation” with Seoul.

China, which is probably North Korea’s closest ally, although relations have been strained by Pyongyang’s weapons programme, warned of more stringent sanctions if the North continues to conduct missile tests.

China’s chief nuclear negotiator, Wu Dawei, is in Seoul for talks with his South Korean counterpart, Kim Hong-kyun. He has underlined the need to discuss the North’s “security concerns”, and said sanctions were insufficient to force a breakthrough in denuclearisation efforts, Yonhap reported, citing diplomatic sources.

In Pyongyang, the North Korean army held a ceremony to pledge its loyalty to Mr Kim ahead of this week’s 105th anniversary of the birth of his grandfather, state founder and late supreme leader Kim Il-sung.

The head of the military, Hwang Pyong-so, said in a speech broadcast live by North Korean Central TV that the North would “mount a pre-emptive nuclear attack on South Korea and the United States and wipe them out without traces if they attempt to launch a war of aggression.”