China has imposed sanctions on nine UK citizens - including five MPs - for spreading what it called "lies and disinformation" about the country.
The group are among the most vocal critics of China in the UK.
It comes in retaliation for measures taken by the UK government on Monday over human rights abuses against the Uighur Muslim minority group, reports BBC
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Boris Johnson said those sanctioned were "shining a light" on "gross human rights violations".
"Freedom to speak out in opposition to abuse is fundamental and I stand firmly with them," the prime minister said in a tweet.
The foreign secretary said if Beijing wanted to "credibly rebut" the claims it should allow UN access to Xinjiang.
Those targeted by China include former Conservative leader Sir Iain Duncan Smith, two peers, a lawyer and an academic.
Sir Iain said he would wear the sanctions "as a badge of honour".
The response by China follows similar sanctions imposed on the European Union, which was part of the co-ordinated action on Monday, along with the UK, the US and Canada.
China has detained Uighurs at camps in the north-west region of Xinjiang, where allegations of torture, forced labour and sexual abuse have emerged.
It has denied the allegations of abuse, claiming the camps are "re-education" facilities used to combat terrorism.
Tory MPs Sir Iain, Nusrat Ghani and Tim Loughton, and peers Baroness Kennedy and Lord Alton, who are all members of the Inter-Parliamentary Alliance on China
Tory MPs Tom Tugendhat and Neil O'Brien, who lead the China Research Group
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Lawyer Sir Geoffrey Nice QC, chair of the Uighur Tribunal, which is investigating atrocities against the minority group
Newcastle University academic Jo Smith Finley, whose research focuses on the Uighurs
They will all be banned from entering China, Hong Kong and Macau, their property in China will be frozen and Chinese citizens and institutions will be prohibited from doing business with them.
Sir Iain said: "Those of us who live free lives under the rule of law must speak for those who have no voice. If that brings the anger of China down upon me then I shall wear that as a badge of honour."
Mr Tugendhat, who chairs the Commons Foreign Affairs Committee, told the BBC: "I view this as a direct assault on British democracy and an attempt to silence the British people who have chosen me to speak for them."
He added that the government had been too soft on China, which he said had been "constantly and continuously seeking to intervene" in the internal matters of the UK.
Ms Ghani told BBC Radio 4's Today programme the move was a "wake-up call" for democratic countries, that China would sanction law-makers who were just doing their job.
She added: "I won't be intimidated. This has now made me even more determined to speak out about the Uighurs."
Academic Dr Smith Finley tweeted: "I have no regrets for speaking out, and I will not be silenced."
Lord Alton said: "The imposition of tit-for-tat sanctions is a crude attempt to silence criticism," adding that the "first duty of a parliamentarian is to use their voice on behalf of those whose voices have been silenced".