Sir Keir Starmer’s ethics tsar must investigate Lord Hermer over potential conflicts of interest, Labour MPs have demanded.

The Attorney General is under fire for refusing to reveal details of payments he has received since becoming a minister, including from former clients.

Lord Hermer has been heavily criticised for his role in handing over the Chagos Islands to Mauritius and suspending some arms sales to Israel.

Ministers and their aides also reportedly refer to Lord Hermer’s department as the “Anti-Government Office” rather than the Attorney General’s Office due to his approach.

He has been dubbed the “Herminator” over claims he blocks legislation

Labour MP Graham Stringer called on Sir Laurie Magnus, the Prime Minister’s independent ethics adviser, to launch a probe into the Government’s top law adviser.

Mr Stringer said: “There are clearly important questions about these potential breaches of the code that demand comprehensive answers.

“I hope that these questions will be answered as quickly as possible by Sir Laurie so that we can end the current uncertainty around the Attorney General’s position.”

Another Labour MP said: “If you’ve got financial interests you should be declaring them, that’s a given. From the local councillor up to the Cabinet minister. No questions. It’s an absolute aberration to have a senior minister avoiding that transparency. I’m surprised this still hasn’t been sorted.”

Lord Hermer has been heavily criticised for his work for controversial clients including jihadi bride Shamima Begum and ex-Sinn Fein leader Gerry Adams.

On Sunday, the Attorney General confirmed he has decided not to refer the sentencing of notorious Southport killer Axel Rudakubana to the Court of Appeal, despite a public outcry.

He stated: “The senseless and barbaric murder of three young girls in Southport last summer shocked our nation.

“No words come anywhere close to expressing the brutality and horror in this case. It was understandable that we received multiple requests to review the sentence under the unduly lenient sentence scheme, which is designed to identify and remedy gross errors made by judges.

“After careful consideration of independent legal advice and consultation with leading criminal barristers and the Crown Prosecution Service, I have concluded that this case cannot properly be referred to the Court of Appeal.

“No one would want the families to be put through an unnecessary further court process where there is no realistic legal basis for an increased sentence. The 52-year sentence imposed by the judge was the second-longest sentence imposed by the courts in English history.

“Rudakubana will likely never be released and will spend the rest of his life in jail. The Government have set out the next steps that must now take place to ensure that these awful murders will be a line in the sand.

“My thoughts today are with the friends and families of Bebe, Elsie and Alice, as well as the other victims – your memories will not be forgotten.”