China and Russia on Thursday vetoed tougher United Nations sanctions against North Korea, rejecting a US effort to punish Pyongyang for testing an intercontinental ballistic missile.

The resolution enjoyed the support of the 13 other members of the Security Council, although some US allies quietly wondered why Washington went ahead with the vote knowing the unflinching opposition from Beijing and Moscow.

China, the closest ally of North Korea, and Russia, whose relations with the West have sunk over its invasion of Ukraine, both said they would have preferred a non-binding statement rather than a fresh resolution with teeth against Pyongyang.

The United States "should not replace one-sided emphasis on the implementation of sanctions alone. It should also work to promote the political solution," said China's ambassador to the United Nations, Zhang Jun.

He warned that sanctions would have humanitarian consequences for North Korea, which recently announced an outbreak of Covid in one of the most closed societies.

Additional sanctions "will not only not help solve the problem but will lead to more negative effects and an escalation of confrontation," he said.

Russia's ambassador, Vassily Nebenzia, accused the United States of ignoring North Korea's appeals to stop "hostile activity" and engage in dialogue.

"It seems that our American and other Western colleagues are suffering from the equivalent of writer's block. They seem to have no response to crisis situations other than introducing new sanctions," he said.

President Joe Biden's administration has repeatedly said it is willing to speak with North Korea without preconditions.

It has found little interest in working-level talks from North Korea, whose leader Kim Jong Un held three high-profile meetings with Biden's predecessor Donald Trump.

While offering talks, the United States said that North Korea had clearly violated a 2017 Security Council resolution that called for further consequences if Pyongyang fires a long-range missile.

The US-drafted resolution would have reduced the amount of oil that North Korea can legally import each year for civilian purposes from four million to three million barrels (525,000 to 393,750 tons).

It would similarly cut imports of refined petroleum from 500,000 to 375,000 barrels.