Yevhen Murayev, 45, told Sky News that the allegation made a fortnight ago by the Foreign Office was false and had had a "devastating" impact on him.

He said he had received death threats and that a number of protests have been held outside the offices of a TV station linked to his family, with demonstrators calling for it to be closed.

Asked why anyone should believe him given that if the claim about him was true and he had just been exposed he would hardly own up to it, Mr Murayev said: "I always thought... a person is not guilty until proven otherwise."

He said no British or Ukrainian security officials had spoken to him about the claim or offered any evidence to substantiate it.

"It is hard to imagine that such an [installed, pro-Russia] administration will be run by a person [me] who has been under Russian sanctions for four years now, who is banned from entry into Russia and who has assets frozen there," he said in an interview on Sunday in Kyiv. "I'm for an independent Ukrainian state."

The Foreign, Commonwealth and Development Office revealed on 22 January that it had "information that indicates" the Kremlin is looking to install a pro-Russia regime in Ukraine.

The unusual statement, based on UK analysis that drew on US-led intelligence, said Mr Murayev "is being considered as a potential candidate".

The former MP has promoted views that align with Russian narratives on Ukraine. Last year, he said Ukrainian President Volodymyr Zelenskiy was controlled by the West and suggested, as Moscow has, that Ukraine might try to regain territory held by Russian-backed separatists in the east of the country by force. Kyiv denies any such plan.

Pressed on the British allegation, though, Mr Murayev said he had never been approached by the Russian intelligence services to be part of any plot against Ukraine.

"I love my country and will never be a transmitter of foreign influence," he said.

Read: West and Russia wage information war over Ukraine

The politician said he thought UK and US spy agencies had been tricked into believing he was some kind of agent by his opponents, claiming that a simple factcheck would have demonstrated it did not make sense given what he described as his tainted status in Russia.

"I'm considered as a threat for Russian interests and security, so to imagine me as a Kremlin puppet - it's not serious," he said.

The politician, who lost his seat in parliament in 2019 but plans to run in elections again, said his lawyers had advised him against trying to sue the Foreign Office over the Russia claim for now, so he is instead going to write a letter demanding it is erased.

"We are preparing the official request to take it [the allegation] down," Mr Murayev said.

"We expect UK officials to apologise for the falsehood that has already had a devastating impact not only on myself but also my supporters and the people I work with.

"I hope that justice will prevail."