An editorial in the Global Times, regarded as a mouthpiece for the ruling Communist Party, said Beijing was hoping for a peaceful outcome but had “very limited influence on the entire situation”.
“The game of chicken between Washington and Pyongyang has come to a breaking point,” it added, saying that if North Korea followed through on vows to carry out a sixth nuclear test, “it is more likely than ever that the situation will cross the point of no return.
“All stakeholders will bear the consequences, with Pyongyang sure to suffer the greatest losses.”
The warning followed a conversation between Xi Jinping and Donald Trump, who has put pressure on China to “properly deal” with its ally’s continued violations of UN sanctions.
“China is very much the economic lifeline to North Korea so, while nothing is easy, if they want to solve the North Korean problem, they will,” the US President tweeted on Saturday.
As North Korea's chief source of trade, food and fuel aid, Beijing has come under increasing pressure to use its influence to dissuade Kim Jong-un from continuing weapons development that has generated international alarm.
But the Chinese government is wary of any measures that could threaten the North Korean regime’s existence, and provoke a potential nuclear war or a new government in Pyongyang beholden to Washington and Seoul.
A spokesperson for the Chinese foreign ministry, Lu Kang, said diplomatic channels remained “smooth [with] normal exchanges” on Tuesday, amid fears of a new test to coincide with the 85th anniversary of the Korean People’s Army.
He urged all sides to exercise restraint and refrain from any actions that could push tensions even higher.
“The current situation on the Korean Peninsula is complicated and sensitive and the tension is high,” he added.
“We urge all sides concerned to keep restrained and calm and refrain from taking actions that could escalate tensions.”
Two American destroyers are conducting joint maritime exercises with ships from the Japanese and South Korean navies, which were to continue on Wednesday in waters both sides of the Korean Peninsula.
The US 7th Fleet said the exercises demonstrate a shared commitment to security and stability in the region and underscore America's flexibility in combining with allied naval forces “in response to a broad range of situations”.
South Korea's military said it was watching troop movements around a northern coastal town where a huge live-fire drill was reportedly launched to mark Tuesday’ anniversary.
The Joint Chiefs of Staff on Tuesday did not directly confirm a report by South Korea's Yonhap news agency, which cited a government source claiming that the North carried out an exercise involving 300 to 400 artillery pieces in an area around Wonsan.
Kim was believed to have observed one of the country's largest artillery drills, following a pattern of key exercises and tests being launched on days of national importance.
From sending new intercontinental ballistic missiles rolling through Pyongyang in a huge parade to threatening an “annihilating strike” on its American enemies, there’s little sign of his government bowing to international pressure.
Following years of threats against South Korea, the US and other enemies, North Korea is continuing efforts to miniaturise a nuclear warhead to be carried by a missile capable of reaching the US mainland.
The most recent test launch failed on the Day of the Sun, marking founder Kim Il-sung’s birth earlier this month, when his grandson viewed new weapons in a huge military parade.
Nikki Haley, the US’s ambassador to the UN, did not rule out a pre-emptive strike to prevent further tests, despite warnings that any military intervention could provoke a “catastrophic response”.
South Korea's envoy for North Korea, Kim Hong-kyun, said he and his Japanese and American counterparts have agreed to “maximise pressure” to prevent further provocations.
The three envoys held talks in Tokyo on Tuesday, where they agreed that China and Russia have vital roles to push nuclear towards denuclearisation.
“We agreed to maximise pressure on North Korea by imposing punitive measures that would be unbearable to them if the North continues further provocations despite our warnings,” Mr Kim said.
There are concerns that China’s ability to secure a peaceful solution to the current spike in tensions has been damaged by repeated snubs by the North, which has ignored its calls to comply with UN resolutions.
Since taking power in 2011, Kim has rarely met with Chinese officials and has yet to visit the country, while his government reportedly ignored a request for a visit by Beijing's top nuclear negotiator, Wu Dawei.
The UN has issued an urgent appeal to lower political and military tensions in the region, where the “war of words” is already having an impact on civilians.
Tomás Ojea Quintana, the special rapporteur for human rights in North Korea, said: “At a time when the international community needs to come together to protect the rights of people in the DPRK, we are instead witnessing a rise in incitement to armed confrontation.
“Statements that feed hatred and polarisation do nothing but undermine opportunities to improve the dire situation of ordinary North Koreans.”
Additional reporting by AP
Join our new commenting forum
Join thought-provoking conversations, follow other Independent readers and see their replies