UK politicians told Chinese government agent 'active' in parliament

The United Kingdom's domestic spy agency has warned that an "agent of the Chinese government" has been actively working to "subvert" the processes of Parliament, a senior British lawmaker says.

Ian Duncan Smith, a former leader of the ruling Conservative Party, said the situation had been revealed by MI5, Britain's domestic counter-intelligence service, which had warned House Speaker Lindsay Hoyle.

Mr Duncan Smith said lawmakers had been informed that the agent was active in Parliament and had been working with a British lawmaker.

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"This is a matter of grave concern," he said.

CNN has reached out to the Chinese embassy in London for comment.

Mr Duncan Smith asked that, in light of the incident, parliament consider beefing up security and deport the Chinese agent.

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He said he heard the individual would not be deported and questioned why further action would not be taken against "an agent of a foreign despotic and despicable power."

"This is surely not good enough," he said.

Mr Duncan Smith is a vocal critic of the Chinese government.

He was sanctioned by Beijing last year for his comments on the treatment of Uyghur Muslims in Xinjiang and is barred from entering the country.

Chinese businesses and citizens are also prohibited from doing business with him.