Home Secretary Suella Braverman was probed by national security officials earlier this year as part of a leak inquiry, it has been reported.
The claim raises further questions about the decision by Rishi Sunak to reappoint Ms Braverman as Home Secretary just six days after she resigned from the job for mishandling sensitive information.
A report in the Daily Mail newspaper claims the rule-breaking minister was previously probed in January as part of a security breach relating to a British spy.
Ms Braverman, who was attorney general at the time, was apparently put under the microscope by the Cabinet Office’s Government Security Group.
The little-publicised unit was investigating a leak related to the Government’s plan to apply for an injunction against the BBC to stop it identifying a spy accused of using his position to terrorise his former partner.
That story said it was Ms Braverman who was seeking the injunction – and MI5 was reportedly “concerned” about how this information had become public.
The inquiry reportedly found no conclusive evidence of who leaked Ms Braverman’s intention to apply for an injunction, with a source telling the newspaper there was “a wide field of potential leakers”.
A Cabinet Office spokesperson said: “We do not comment on alleged leak investigations.”
The new claims come after Ms Braverman admitted to a breaching the ministerial code by sending an official document from a personal email.
Claiming her actions were a “technical infringement” of the rules, she said: “I have made a mistake; I accept responsibility; I resign.” She returned to the same job less than a week later.
Commenting on the Home Secretary’s re-appointment, Liberal Democrat leader Ed Davey said he had been told that Ms Braverman’s nickname among officials on Whitehall was “leaky Sue”.
“There’s a slight sort of shock that when a Home Secretary resigns for effectively breaching national security, not just the ministerial code, it was far more serious than that, that somehow the new Prime Minister thinks he’s okay to bring it back straightaway,” he told podcast The News Agents.
“I’m genuinely gobsmacked by that decision of the new Prime Minister. And the answers were not forthcoming from the government today.”
He added: “Her nickname we’re told is Leaky Sue and for a Home Secretary to even have that nickname after a relatively short time in office, I think says it all.”
Yvette Cooper, Labour’s Shadow Home Secretary the allegations against Ms Braverman were “extremely serious” and demanded “an urgent investigation into the Home Secretary’s security breaches”.
She added: “The Prime Minister needs to say whether he knew about these allegations when he re-appointed her. Ignoring warnings about security risks when appointing a Home Secretary is highly irresponsible and dangerous. We need answers now.”
But Tory chairman Nadhim Zahawi said Ms Sunak was right to give Ms Braverman a “second chance”.
“She admitted her mistake, she resigned. A new Prime Minister came in, looked at the information and decided that he wants to give her a second chance. It think that is the right decision. Redemption is a good thing,” he told Sky News.
He refused to be drawn on reports that officials, including the Cabinet Secretary Simon Case, had expressed concern about her reappointment so soon after her resignation for breaching the ministerial code.
“Officials raise concerns and raise points with secretaries of state, with ministers, all the time. I think they should be allowed to do that,” he said.
But Conservative MP Mark Pritchard, a former member of parliament’s influential intelligence and security committee, said: “MI5 need to have confidence in the Home Secretary – whoever that might be.
“It’s a vital relationship of trust, key to the UK’s security and democratic oversight of MI5. Any breakdown in that relationship is bad for the security service and the government. It needs to be sorted ASAP.”
