Trump's new team is prioritising policy talk with Nigel Farage before Theresa May
Arron Banks, UKIP's millionaire donor, told the Telegraph that Steve Bannon, Trump's newly-appointed chief strategist, will "run ideas" past the UKIP leader before consulting the prime minister.
Farage and Banks met Bannon and Trump in New York on Saturday to discuss policy, and Farage campaigned for the Republican in the run-up to the election. Banks said the pair were "best mates" who text each other "every day."
As well as Trump and Farage sharing a close relationship, the UKIP leader is closely linked to Bannon through a network of contacts at the right-wing Breitbart News organisation, where Bannon is the executive chairman.
Banks told the Telegraph that "Nigel has a hotline to the president and the president's chief adviser," and said that the PM's team were "stumped because whatever they say or do, you can't undo a relationship with Steve Bannon that goes back years."
"There is no doubt about it that Steve Bannon will talk to Nigel Farage before any other British politician and run stuff by them," he said.
He added: "When he opened the door, it was like "come on in Nigel." We just sat there chatting for an hour and we ended the meeting. They are as close as two people can be in politics."
Banks' comments came after May ruled out Farage having any involvement in the official UK-US relationship.
The PM's spokesperson said that Trump wanted to replicate the warm relationship enjoyed by Margaret Thatcher and Ronald Reagan, and added: "I don't remember there being a third person in that relationship."
Farage reacted angrily at his offer to "mend fences" after the PM's colleagues - even her own aides - made rude remarks about Trump in the run-up to the election.
Farage responded angrily and said that excluding him from official communication channels would betray the "national interest."
Members of May's own cabinet appear to agree - some have reportedly vowed to defy the PM and hold talks with Farage about his talks with the president-elect.
A ministerial source told the Telegraph: "If he wanted to come along and volunteer information then I am sure the Government would listen to what he has to say."