War of words: North Korean leader Kim Jong Un and US President Donald Trump © AFP

The Trump administration has raised the pressure on Moscow and Beijing to isolate the North Korean regime by imposing sanctions on an array of Chinese and Russian companies and individuals it has accused of helping Pyongyang develop nuclear weapons.

The measures announced on Tuesday come just weeks after the UN Security Council imposed tough new sanctions on North Korea in response to the country’s first two tests of a functioning intercontinental ballistic missile — measures backed by China and Russia.

They also come after an unprecedented war of words between Donald Trump and his North Korean counterpart, Kim Jong Un, in which the US president promised “fire and fury like the world has never seen” if Pyongyang threatened the US. This was followed by a North Korean threat to fire missiles at US-controlled Guam.

The step reflects an urgency that has gripped Washington over North Korea. Political pressure is increasing, including from some west-coast congressmen, over fears that Pyongyang is now capable of hitting the US mainland after a series of successful missile tests.

“This is a signal from the Trump administration that, while Chinese and Russian compliance with the new UN Security Council sanctions is useful, it is not sufficient,” said Dennis Wilder, a former top White House Asia adviser to George W Bush. “Trump feels the window for stopping North Korea from having an ICBM capable of striking the US is narrow.”

A Chinese embassy spokesperson said Beijing “opposes unilateral sanctions out of the UN Security Council framework,” arguing China was implementing the UN resolutions “in their entirety”.

“We strongly urge the US to immediately correct its mistake, so as not to impact bilateral co-operation on relevant issues,” the spokesperson said.

The US Treasury imposed sanctions on 10 companies and six individuals. Their activities included providing North Korea with materials for weapons, buying coal and other resources that generate cash for Pyongyang, facilitating the export of North Korean workers, and helping companies in the hermit state access the US financial system.

“It is unacceptable for individuals and companies in China, Russia, and elsewhere to enable North Korea to generate income used to develop weapons of mass destruction and destabilise the region,” said Steven Mnuchin, Treasury secretary.

In announcing what are known as “secondary sanctions” — penalties against those doing business with a rogue regime rather than against the regime itself — Mr Mnuchin said the administration would continue to punish companies that help North Korea evade sanctions by cutting them off from the US financial system.

In June, the Treasury sanctioned the Bank of Dandong, a small Chinese financial institution based near the border with North Korea, for helping Pyongyang to engage in money laundering. The move prompted an angry reaction from Beijing.

Mr Trump and Xi Jinping, Chinese president, have sparred repeatedly over Beijing’s ability to discipline Mr Kim. While China has taken some measures against North Korea, the White House believes they have not gone far enough. Speaking at the G20 in Hamburg last month, Rex Tillerson, secretary of state, said Washington also wanted Russia to be more assertive.

The targets of the new sanctions include:

  • Dandong Rich Earth Trading, a Chinese company accused of importing vanadium, a rare metal used to reinforce steel;

  • Gefest-M, a Russian company accused of procuring metals for a North Korean company involved in weapons development;

  • Mingzheng International Trading, a China and Hong Kong-based bank that allegedly provides financial services for Foreign Trade Bank, the main North Korean foreign exchange bank.

Three Chinese coal companies are accused of breaching UN sanctions by importing nearly $500m of the fuel from North Korea. The Treasury said one of the companies, Dandong Zhicheng Metallic Metals, used some of the proceeds of its sales to procure nuclear and missile components for North Korea.

The Russian embassy in Washington did not immediately reply to requests for comment. But a member of Russia’s upper house of parliament criticised the sanctions and called for a response from Moscow.

“These sanctions are illegal in themselves, because the only thing recognised by international law is the sanctions of the UN Security Council,” said Andrei Klimov, a Russian senator. “We must react in principle to this insane and confrontational policy. The toolbox is rich, let’s hope that we will act consistently, reasonably, professionally and effectively.”

Additional reporting by Henry Foy in Moscow

Follow Demetri Sevastopulo on Twitter: @dimi

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