Nigel Farage has dismissed as "conspiratorial nonsense" claims made to a US committee that he had more than one meeting with Julian Assange.
The former UKIP leader was seen leaving the Ecuadorian embassy in London, where Mr Assange is living, in March 2017.
But the House Intelligence Committee has released testimony containing claims Mr Farage had made "additional trips" to the embassy.
It also claims he "provided data" to the Wikileaks founder.
The claims are made by Glenn Simpson, co-founder of US political research firm Fusion GPS in evidence to the committee - which is conducting one of several probes into alleged meddling by Moscow in the US presidential election, and any collusion with the Trump campaign.
All of them have been dismissed by the US president as "fake news".
Fusion GPS employed former MI6 officer Christopher Steele, who produced a dossier containing unconfirmed allegations about Mr Trump and Russia - claims strongly denied by the US President.
Mr Simpson told the committee his interest in the Trump campaign's links to UKIP and WikiLeaks were a separate matter from Mr Steele's investigations.
In testimony to the committee in November, which has just been published, he said: "I've been told and have not confirmed that Nigel Farage had additional trips to the Ecuadorian embassy than the one that's been in the papers and that he provided data to Julian Assange."
Asked what kind of data, he replied: "A thumb drive."
Mr Farage responded: "This is conspiratorial nonsense." In October he described reports suggesting that he was a "bag man" running messages between President Trump and Julian Assange as a "complete lot of baloney".
He said he had met Mr Assange after it was organised by LBC - the radio station on which he has a show - and he had taken his producer with him.