The US State Department has announced visa restrictions for a number of Chinese government officials and members of the ruling Communist Party, writes Reuters.

Chinese politicians are suspected of harbouring Islamist minorities in northwest China's Xinjiang province.

Among those sanctioned is the Communist Party leader in Xinjiang, Chen Jing Guo, who is among the 25 members of the Politburo, China's largest authority.

In a statement describing the "highly repressive campaign" of detention, mass surveillance, "draconian controls" on religious and cultural expression, and coercion, US Secretary of State Mike Pompeo announced "visa restrictions on Chinese government and Communist Party officials who are believed to be responsible for, or complicit in, the detention or abuse of Uighurs, Kazakhs or other members of Muslim minority groups in Xinjiang, China."

"Family members of such persons may also be subject to these restrictions," he added, quoted by the CNN.

Washington has announced that it will not distribute a list of sanctions, but news of the restrictions imposed has led to a decline in world stock markets.

Traders say such moves significantly reduce the chances of the US and China reaching an agreement to end the trade war between them.

"The United States calls on the People's Republic of China to immediately end its campaign of repression in Xinjiang, release all those arbitrarily detained, and cease efforts to coerce members of Chinese Muslim minority groups residing abroad to return to China to face an uncertain fate," Pompeo wrote. "The United States will continue to review its authorities to respond to these abuses." Secretary of State Mike Pompeo wrote.