BEIJING, CHINA -- Twitter said Thursday it has locked the account of the Chinese embassy in the U.S., over a tweet claiming Uighur women were no longer "baby-making machines" after their minds had been "emancipated."

A Twitter spokesperson told AFP it took action against the tweet for "violating our policy against dehumanization".

More than one million Uighurs and other mostly Muslim minorities are believed to be held in re-education camps in the country's northwestern Xinjiang region, where China is also accused of forcibly sterilising women.

China denies the accusations and says the facilities in the region are not camps, but job training centres to steer people away from terrorism.

On January 7, the Chinese embassy in the U.S. tweeted that "in the process of eradicating extremism", the minds of Uighur women "were emancipated and gender equality and reproductive health were promoted, making them no longer baby-making machines."

The incendiary tweet, which has since been hidden after outrage ripped across the internet, included a link to an article by state media outlet China Daily that claimed the "eradication of extremism has given Xinjiang women more autonomy" over whether to have children.

Twitter policy states that it prohibits "dehumanization of a group of people based on their religion, caste, age, disability, serious disease, national origin, race, or ethnicity".

The social media company said the embassy's account is temporarily locked until the tweet deemed in violation of this policy is deleted.

On Thursday, China's foreign ministry said it did not understand Twitter's decision to impose the restrictive measures, saying China was a "major victim" of "fake and ugly information... in relation to the Xinjiang issue."

"We hope Twitter will uphold the principles of objectivity and fairness... strengthen its screening, and screen out what is actually disinformation," said spokeswoman Hua Chunying.

The latest suspension comes as the US and China eye the future, after relations hit their lowest point in decades under President Donald Trump -- with both sides crossing swords over issues from the origins of Covid-19 to Beijing's policies in Hong Kong and Xinjiang.

On Tuesday, in the twilight hours of Trump's administration, the U.S. declared China was carrying out genocide against Uighurs and other mostly Muslim people.

It urged international bodies to take up cases over China's treatment of the minority group.

Beijing dismissed the U.S. allegations as "outrageous lies" and "poison", and on Wednesday sanctioned more than two dozen officials and members of former president Trump's cabinet, including his secretary of state Mike Pompeo.

Twitter's latest act also adds to already difficult relations between China and major US tech companies, with popular social media platforms such as Twitter and Facebook, as well as search engines like Google, blocked in China for years.