The businessman said he thought Ms Cadwalladr made the remarks due to “personal animus”, adding: “This was a calculated and deliberate attack upon me.”

Mr Banks’s claim is being heard at the High Court this week.

While he said he expected some personal criticism due to his involvement in the Leave campaign, he argued that there are “boundaries that must be observed”.

His witness statement added: “I consider it wrong for untrue statements to be made which give a false and seriously damaging account to unsuspecting members of the public, who may not be aware of the truth, who will then be misinformed.

“This is why I have continued with my action against Carole in relation to the untrue and highly defamatory statements she made about me in the TED Talk and repeated in the tweet.”

‘No hidden agenda’

Mr Banks was questioned on Friday by lawyers for Ms Cadwalladr, who asked what he expected the nature of the meeting to be when he was invited to the Russian Ambassadors’ residence in 2015.

He said: “I thought that if there was an invitation to visit the Russian ambassador then it would be very interesting. I certainly wasn’t overthinking it the way you are suggesting. I didn’t automatically think there was a hidden agenda.”

Lawyers for Ms Cadwalladr said she did not intend to allege that Banks had received funding from the Russian government in relation to the Brexit campaign, and that her comments were “part of a discussion about matters of the highest public interest”. Ms Cadwalladr is running a public interest defence and is not alleging that her statement was true.

The case continues on Monday.