The Ukip leader had said he would be retiring from frontline politics but appears to to be having second thoughts.
The Conservatives are facing a probe into their election expenses during the campaign for the Kent constituency and if they are upheld a by-election could be triggered.
The moment Craig Mackinlay won the South Thanet seat
Mr Farage said that if that was the case he would return to the fray despite announcing in summer that he was to stand down as Party leader.
In an interview with the Mail on Sunday, Mr Farage said the Conservatives were becoming anxious over the possibility of a rerun in Thanet should the investigation uphold claims that certain expenses were not properly reported.
He said: “I suspect one of the reasons Downing Street is being so vile about me – just when I can play a positive role with Trump – is because they are worried this may come back to bite them.”
Asked if he would stand as the party’s candidate in any by-election, he replied: “I’d have to.”
He joked that he could even bring Donald Trump over to campaign on his behalf.