Nigel Farage is sharing his London house with a female French politician who heads a think tank at the centre of an illegal Ukip funding probe.
Laure Ferrari - who runs the Institute for Direct Democracy in Europe (IDDE) - has been living in the former Ukip leader's £4million house in Chelsea for the past week, according to The Mail on Sunday.
Mr Farage told the paper that he was helping her out because she needed accommodation and had nowhere else to stay.
"She is someone I have worked with and known well for a long time who wanted somewhere to stay for a week that wouldn't cost her any money.
"It's a working relationship," he was quoted as saying.
Last November the Electoral Commission announced it was opening an investigation into whether Ukip had accepted "impermissible donations" from IDDE and the Alliance for Direct Democracy in Europe (ADDE), the political party it is affiliated to.
It followed an audit by the European Parliament which concluded that ADDE and IDDE used EU grant funding for the benefit of Ukip in breach of its rules.
The claims have been strongly contested by Ukip.
Ms Ferrari, who first became involved in politics as a result of a chance meeting with Mr Farage 10 years ago while she was working as a waitress in Strasbourg, said she had been forced to move out of her own flat after the European Parliament stopped IDDE's funding.
"I have no trustworthy friends in London who could have hosted me.
"I asked and he accepted. He is just trying to be helpful," she told The Mail on Sunday.
Asked by the newspaper whether he had slept with Ms Ferrari, Mr Farage said he was not prepared to answer "ludicrous questions".
Last month Mr Farage told paper that he spent most week nights at a "bachelor pad" and denied that he had split from his German-born wife, Kirsten.
