Boris Johnson's ethics adviser Lord Geidt has resigned following controversy over whether the Prime Minister broke ministerial code.

Lord Geidt tendered his resignation to the Prime Minister in a short statement on Wednesday.

The brief announcement was published on the UK Government’s website.

“With regret, I feel that it is right that I am resigning from my post as independent adviser on ministers’ interests,” it read.

Lord Geidt resigns 'with regret' as Boris Johnson's ethics adviser

The National Wales: Boris Johnson. Credit: PABoris Johnson. Credit: PA

The news comes after he declined to deny to MPs whether he had considered resigning over Mr Johnson’s response to being fined for breaching lockdown rules.

Lord Geidt told the Public Administration and Constitutional Affairs Committee that he had felt “frustration” over the partygate scandal.

“I am glad that the Prime Minister was able to respond to my report and in doing so addressed aspects of the things about which I was clearly frustrated,” he told the committee.

“Resignation is one of the rather blunt but few tools available to the adviser. I am glad that my frustrations were addressed in the way that they were.”

It was reported that Lord Geidt had threatened to quit last month after the publication of the Sue Gray report into lockdown breaches in Whitehall unless Mr Johnson issued a public explanation for his conduct.

This is not the first time that Mr Johnson’s ethics adviser has resigned during his three years as Prime Minister.

Lord Geidt is the second person following Sir Alex Allan quitting in 2020.

Sir Allan resigned after Mr Johnson refused to accept his finding that Home Secretary Priti Patel had bullied civil servants.

Boris Johnson is said to be totally surprised by Lord Geidt’s resignation as his ethics chief.

A senior source in No 10 told the PA news agency: “We are surprised, this is a mystery to the PM.

“Only on Monday he said he would like to stay on for another six months.”