Donald Trump’s administration is under domestic pressure to hit China with new economic sanctions over its alleged internment of one million Uighurs against their will.

Marco Rubio, the Republican senator and former presidential hopeful, and 16 other US congressmen have penned a letter urging sanctions, according to The Wall Street Journal.

The politicians want Mr Trump’s administration to use the Global Magnitsky Act, passed after the death of Russian tax accountant Sergei Magnitsky in 2009, to punish Beijing.

It follows a damning report from the United Nations’s human rights experts that estimated up to a million Uighurs were being held in extra-legal detention in China’s far western Xinjiang province.

The Uighurs are a Turkic ethnic group who live in east and central Asia. The Uighurs and other mainly Muslim minorities are allegedly being targeted by the Chinese authorities, including being held captive in detention centres or political re-education camps according to experts. 

Beijing has never confirmed existence of the camps. Chinese officials say there is a serious threat from Islamist militants and separatists in Xinjiang province and insist they are acting as any other nation would.

The letter from the congressmen said China’s behaviour towards the Uighurs “requires a tough, targeted and global response”, according to The Wall Street Journal.

It went on: “No Chinese official or business complicit in what is happening [in Xinjiang] should profit from access to the United States or the US financial system.”

The report from the UN Committee on the Elimination of Racial Discrimination criticised China’s "broad definition of terrorism and vague references to extremism and unclear definition of separatism in Chinese legislation".

It warned the definition could be used against those peacefully exercising their rights and facilitate "criminal profiling" of ethnic and religious minorities, including Uighurs, Tibetans and Mongolians.

In its conclusions, the panel said it was alarmed by "numerous reports of detention of large numbers of ethnic Uighurs and other Muslim minorities held incommunicado and often for long periods, without being charged or tried, under the pretext of countering terrorism and religious extremism".

Nicolas Marugan, a panel member, told Reuters Television: “We are recommending to China if this practice exists, to halt it. We are asking China to release people if they don’t have a legal ground to be detained.”

Hua Chunying, the Chinese foreign ministry spokesman, pushed back on the UN report, saying: "These comments … were based on so-called information that is yet to be verified and has no factual basis.”

She added: "The sense of security and the fulfilment of people in Xinjiang has been greatly enhanced. As for all the preventive security measures we’ve taken, many countries around the world do the same."

The US State Department is yet to formally respond to the congressmen’s letter. It comes at a time when Mr Trump is already in an open trade war with China, hitting the country with billions of dollars’ worth of tariffs while seeking to negotiate better terms of trade.