North Korean state media warned on Tuesday of a nuclear attack on the United States at any sign of American aggression as a U.S. Navy strike group steamed toward the western Pacific.

President Donald Trump, who has urged China to do more to reign in its impoverished neighbor, said in a Tweet that North Korea was 'looking for trouble' and the United States would 'solve the problem' with or without China's help.

Tension has escalated sharply on the Korean peninsula amid concerns that reclusive North Korea may soon conduct a sixth nuclear test and after Washington said at the weekend it was diverting U.S. Navy strike group Carl Vinson from port calls to Australia toward the Korean peninsula as a show of force.

North Korean state media has warned of a possible nuclear attack if the country becomes the target of American aggression. Above, North Korean leader Kim Jong Un pictured above on Tuesday, attending a meeting of the Supreme People's Assembly in Pyongyang

Officials stand and applaud as Kim Jong Un presides over the parliament meeting on Tuesday

President Trump has ordered the U.S. Navy strike group Carl Vinson towards the Korean peninsula, in response to the country's continued missile tests

U.S. officials have stressed that stronger sanctions are the most likely U.S. course to press North Korea to abandon its nuclear program but Washington has said all options, including military ones, are on the table and that a U.S. strike last week against Syria should serve as a warning to Pyongyang.

Our revolutionary strong army is keenly watching every move by enemy elements with our nuclear sight focused on the U.S. invasionary bases not only in South Korea and the Pacific operation theatre but also in the U.S. mainland.

North Korea's official Rodong Sinmun newspaper said the country was prepared to respond to any U.S. aggression.

'Our revolutionary strong army is keenly watching every move by enemy elements with our nuclear sight focused on the U.S. invasionary bases not only in South Korea and the Pacific operation theatre but also in the U.S. mainland,' it said.

South Korea's acting President Hwang Kyo-ahn warned of 'greater provocations' by North Korea and ordered the military to intensify monitoring and ensure close communication with Washington.

'It is possible the North may wage greater provocations such as a nuclear test timed with various anniversaries including the Supreme People's Assembly,' said Hwang, acting leader since former president Park Geun-hye was removed amid a graft scandal.

The US President wrote the message on Twitter after revealing he had urged his Chinese counterpart Xi Jinping to pressure its neighbor and close ally in to stopping its nuclear program

The Chinese army has deployed 150,000 troops to the Yalu River Bridge at the North Korean border in anticipation of a wave of refugees from North Korea if war breaks out. Meanwhile, the US Navy has moved the USS Carl Vinson aircraft carrier strike group from Singapore to the North Korean peninsula

Trump said in a Tweet that a trade deal between China and the United States would be 'far better for them if they solved the North Korea problem'.

'If China decides to help, that would be great,' he said. 'If not, we will solve the problem without them!'

Trump and his Chinese counterpart Xi Jinping met in Florida last week and Trump pressed Xi to do more to rein in North Korea.

China's ambassador to the United Nations, Liu Jieyi, repeated China's call for a return to dialogue with North Korea.

U.S. military soldiers gather at the U.S.-South Korea joint Exercise Operation Pacific Reach in Pohang, South Korea on Tuesday

U.S. Marine soldiers walk around military vehicle in the U.S.-South Korea joint Exercise Operation Pacific Reach in Pohang, South Korea on Tuesday

'The situation is tense and we certainly want a peaceful solution and we believe that it is highly important to move toward denuclearization, to maintain peace and stability and it´s time that different sides sit down to talk about achieving these objectives,' he told Reuters.

Asked about Trump linking a trade deal to China´s help with North Korea: 'We need to look at the situation on the Korean Peninsula as something that we should work together on.'

North Korea convened a Supreme People's Assembly session on Tuesday, one of its twice-yearly sessions attended by leader Kim Jong Un, and reported a successful national budget execution and personnel appointments, the official KCNA news agency said.

The agency made no mention of North Korea's nuclear weapons programme or being under threat from the United States.

North Korean students participate in a mass dance event to mark the occasion of the late North Korean leader Kim Jong Il's election as chairman of the National Defense Committee on Sunday, April, in Pyongyang

On Saturday, the country will celebrate the birthday of the country's founding leader, the late Kim Il Sung

North Korea often marks important anniversaries with tests of its nuclear or missile capabilities in breach of U.N. Security Council resolutions

South Korean officials sought to quell talk in social media of an impending security crisis.

DEFENSE SECRETARY: NAVY STRIKE TEAM WAS NOT MOVED FOR SPECIFIC REASON The movement of a U.S. Navy strike group toward the western Pacific Ocean is not tied to a specific event and is a prudent move, U.S. Defense Secretary Jim Mattis said on Tuesday. ' As far as the movement of the (Carl) Vinson, she is stationed there in the Western Pacific for a reason, she operated freely, up and down the Pacific, and she is just on her way up there because that is where we thought it was most prudent to have her at this time,' Mattis told a Pentagon press briefing. 'It is not a specific demand signal or a specific reason why we are sending her up there,' Mattis said. The Carl Vinson will take more than a week to move toward the Korean peninsula, as concerns grow about North Korea's advancing weapons program. Advertisement

'We'd like to ask for precaution so as not to get blinded by exaggerated assessment about the security situation on the Korean peninsula,' Defence Ministry spokesman Moon Sang-kyun said.

Saturday is the 105th anniversary of the birth of Kim Il Sung, North Korea's founding father and grandfather of the current ruler.

A military parade is expected in Pyongyang to mark the day. North Korea often also marks important anniversaries with tests of its nuclear or missile capabilities in breach of U.N. Security Council resolutions.

Men and women in colorful outfits were singing and dancing on the streets of Pyongyang, illuminated by better lighting than seen in previous years, apparently practicing for the parade.

Syrian President Bashar al-Assad sent congratulations, lambasting 'big powers' for their 'expansionist' policy.

'The friendly two countries are celebrating this anniversary and, at the same time, conducting a war against big powers' wild ambition to subject all countries to their expansionist and dominationist policy and deprive them of their rights to self-determination,' the North's KCNA news agency quoted his message as saying.

North Korea's foreign ministry said the approach of the U.S. Navy strike group showed Washington's 'reckless moves for invading had reached a serious phase'.

'We never beg for peace but we will take the toughest counteraction against the provocateurs in order to defend ourselves by powerful force of arms and keep to the road chosen by ourselves,' an unidentified ministry spokesman said.

U.S. officials said at the weekend the carrier group would take more than a week to reach waters near the Korean peninsula.

A statement from U.S. forces in South Korea on Tuesday said General Vincent Brooks, commander of United States Forces Korea, would not attend a Congressional hearing expected for later this month because of the 'security situation on the Korean Peninsula.' The statement said the step was not unprecedented.

North and South Korea are technically still at war because their 1950-1953 conflict ended in a truce, not a peace treaty. North Korea regularly threatens to destroy South Korea and its main ally, the United States.