US President Donald Trump’s latest threat of additional 100 per cent tariffs on Chinese goods in response to new curbs on rare earth exports has raised further questions about whether any meaningful improvement in relations is possible.

Trump also threatened to cancel a proposed meeting with his Chinese counterpart Xi Jinping at the end of the month and put export controls on “any and all critical software” in response to Beijing’s new restrictions on rare earth exports announced on Thursday.

As part of the latest tit-for-tat between the two countries, China also imposed new port fees that primarily target US-built, flagged, owned or operated vessels, and launched an antitrust investigation into the tech firm Qualcomm on Friday.

Similar port fees, announced earlier this year, are due to come into effect in the US later this month. Washington has also expanded export controls designed to prevent advanced technology and other dual-use goods being diverted to China.

“Trump was furious and embarrassed as he had previously boasted of resolving the rare earth issue in negotiations with China,” said He Weiwen, a former US-based diplomat and senior fellow at the think tank Centre for China and Globalisation.

He said the fact that the US president was once again threatening to raise tariffs suggested he had few other tools to put pressure on China.