BEIJING/TOKYO: Chinese President Xi Jinping called for a peaceful resolution of rising tensions on the Korean peninsula in a telephone conversation with US President Donald Trump on Wednesday, as a US aircraft carrier strike group steams towards the region.

Xi’s call with Trump came after an influential state-run Chinese newspaper warned that the Korean peninsula was the closest it has been to a “military clash” since Pyongyang’s first nuclear test in 2006.

Tension has escalated sharply amid concerns that reclusive North Korea could soon conduct a sixth nuclear test or more missile launches and Trump’s threat of unilateral action to solve the problem.

Trump had already ordered the USS Carl Vinson aircraft carrier group to head for the Korean peninsula in an attempt to deter North Korea’s nuclear and long-range missile ambitions, which it is developing in defiance of United Nations resolutions and sanctions.

Wednesday’s call between Xi and Trump came hard on the heels of their first face-to-face meeting in Florida last week. It was not immediately clear who initiated the call.

Trump, who has urged China to do more to rein in North Korea, had warned earlier on Twitter that Pyongyang was “looking for trouble” and that the United States would “solve the problem” with or without Beijing’s help.

Xi stressed that China “is committed to the target of denuclearisation on the peninsula, safeguarding peace and stability on the peninsula, and advocates resolving problems through peaceful means,” Chinese state broadcaster CCTV said of the exchange between the two leaders.

“China is willing to maintain close communication and coordination with the US side,” Xi said.

Earlier on Wednesday, two sources in Tokyo said Japan’s navy planned exercises with the Carl Vinson carrier group in a joint show of force, amid concern over the rapid pace of North Korea’s ballistic missile development.

China’s Global Times newspaper also said in an editorial North Korea should halt any plans for nuclear and missile activities “for its own security”. While widely read in China and run by the ruling Communist Party’s official People’s Daily, the Global Times does not represent government policy.

The editorial noted Trump’s recent decision to launch 59 Tomahawk missiles at a Syrian airfield in response to a deadly gas attack last week.

“Not only (is) Washington brimming with confidence and arrogance following the missile attacks on Syria, but Trump is also willing to be regarded as a man who honours his promises,” the Global Times said.

“The US is making up its mind to stop the North from conducting further nuclear tests. It doesn’t plan to coexist with a nuclear-armed Pyongyang,” it said. “Pyongyang should avoid making mistakes at this time.”

More tests coming?

North Korean state media warned on Tuesday of a nuclear attack on the United States at any sign of American aggression.

Officials from the North, including leader Kim Jong Un, have indicated an intercontinental ballistic missile test or something similar could be coming.

North Korea launched a long-range rocket carrying a satellite on April 13, 2012, marking the anniversary of the birth of North Korea’s founding president Kim Il Sung.

Saturday will be the 105th birthday of the founding leader.

Two sources in Japan said the Japanese Maritime Self Defence Force (MSDF) and the US Navy could conduct helicopter landings on each other’s ships, as well as communication drills, as the US ships pass through waters close to Japanese territory.

“Japan wants to dispatch several destroyers as the Carl Vinson enters the East China Sea,” one of them said.

One of the people who spoke to Reuters has direct knowledge of the plan, while the other has been briefed on the exercises.

MSDF officials did not respond immediately when asked for comment.

A senior Japanese diplomat said it appeared the US position was to put maximum pressure on North Korea to reach a solution peacefully and diplomatically.

“At least, if you consider overall things such as the fact that the US government has not put out warnings to its citizens in South Korea, I think the risk (of military action) at this point is not high,” said the diplomat, who asked not to be identified.

South Korea’s acting president, Hwang Kyo-ahn, has warned of “greater provocations” by North Korea and ordered the military to intensify monitoring.

The North fired a liquid-fuelled Scud missile this month, the latest in a series of tests that have displayed Pyongyang’s ability to launch attacks and use hard-to-detect solid-fuel rockets.

North Korea remains technically at war with the United States and its ally South Korea after the 1950-1953 Korean conflict ended in a truce, not a peace treaty. It regularly threatens to destroy both countries.

The Carl Vinson strike group, which cancelled a planned visit to Australia, is sailing from Singapore. The 100,000-tonne Nimitz-class vessel is powered by two nuclear reactors and carries almost 100 aircraft.

Japan’s navy, the second largest in Asia after China, is made up mostly of escort destroyers, but includes four large helicopter carriers.