Nigel Farage is facing a probe from the Parliament standards watchdog over a possible breach of the MPs code of conduct.
Parliamentary Standards Commissioner Daniel Greenberg launched the inquiry over a potential infringement of the rules regarding a “registration of interest”.
The commissioner’s website indicates the investigation against the Reform UK leader opened on Monday.
The possible breach by Farage regards Rule 5 of the MPs code of conduct.
It states MPs must declare any change to their interests within 28 days.
However, an inquiry does not mean rules have been broken.
The inquiry comes after Greenberg was urged to investigate whether Farage should have declared support from a PR firm whose former boss is now an official for US President Donald Trump.
The inquiry has not made clear which declaration, or non-disclosure, is being investigated.
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An inquiry does not mean rules have been broken
A Farage spokesman said “following a complaint from a member of the House of Lords, the Commissioner for Standards is doing his job”.
Rule 5 of the MPs’ code reads: “Members must fulfil conscientiously the requirements of the House in respect of the registration of interests in the Register of Members’ Financial Interests.
“New Members must register all their current financial interests, and any registrable benefits (other than earnings) received in the 12 months before their election within one month of their election, and Members must register any change in those registrable interests within 28 days.”
The Reform leader told The Telegraph he could “explicitly state” that the matter did not relate to “any undeclared income”.
Rachel Reeves faced a similar investigation by the standards watchdog earlier this year
Farage would be required to rectify the error by updating the MPs’ register of interests if found guilty of a breach.
Tougher sanctions, including a suspension, can be implemented by the Commons standards committee for serious breaches.
Rachel Reeves faced a similar investigation by the standards watchdog earlier this year over her declaration of free theatre tickets when she failed to declare them within the 28-day deadline for registering gifts.
She later acknowledged the mistake and apologised for the error.