Somerton and Frome MP David Warburton has apologised after an investigation found he broke strict rules around declaring a £150,000 loan from a Russian-born businessman.
The cash came from Castlebrook Associates Limited in 2017. At the time, Mr Warburton failed to register or declare the payment.
In response to an investigation by the Parliamentary Commissioner for Standards Kathryn Stone, the MP said he did not register the loan at the time because it was "entirely unconnected" with his role as an MP or "any parliamentary activities".
Ms Stone said she was satisfied on the evidence that the loan had not influenced Mr Warburton's words or actions as an MP.
The Commissioner reported that Mr Warburton has written to her accepting the decision and "acknowledging and apologising for the breach".
As well as apologising, the MP has now registered the loan in the House of Commons Register of Members' Financial Interests.
David Warburton currently sits as an independent MP having had the Conservative whip withdrawn earlier this year following allegations of sexual harassment and cocaine use. He denied any wrongdoing.
He has not voted in the Commons since the end of March 2022 when the allegations emerged.