Rishi Sunak begins his first full week as Prime Minister facing questions about his decision to bring Suella Braverman back as Home Secretary, calls for a U-turn over a climate summit snub and concerns about national security at the heart of Government.

The Prime Minister is considering reversing his decision not to attend the United Nations climate conference in Egypt next week, with environment minister Mark Spencer saying Mr Sunak would go “if his diary allows”.

While Mr Sunak is focusing on domestic issues, including preparations for the November 17 autumn statement, he also faces political challenges including the backlash over the reappointment of Ms Braverman.

The Government’s climate tsar Alok Sharma said he was “disappointed” by the decision not to attend the Cop27 summit, while Tory former chancellor George Osborne asked why Mr Sunak would “trash” the party’s record on the environment.

With US President Joe Biden expected to attend, and reports suggesting Mr Sunak’s arch-rival Boris Johnson could go to the summit, the Prime Minister is weighing up whether to go.

Mr Spencer said the possibility of Mr Johnson going was not a “consideration” for the Prime Minister.

“I think, actually, he’ll be looking at how much he’s got in his inbox,” he told LBC.

“But I think the fact that Boris is thinking of going is a demonstration of how seriously the Conservative Party and the Conservative Government takes these things.”

Mr Spencer told Sky News he would like to see the Prime Minister go to Cop27 “if he’s got time” but “he’ll make that call and I’m sure it’ll be the right one”.

Meanwhile, the way Tory ministers have handled sensitive information remained in the spotlight.

Ms Braverman was forced to quit as Home Secretary under Liz Truss after she emailed a potentially market-sensitive draft written ministerial statement to veteran backbench Tory Sir John Hayes, a fellow right-winger, from a personal email account.

But less than a week later she was back in the role in Mr Sunak’s first Cabinet.

In another information security issue, it emerged in the Mail on Sunday that Ms Truss’ personal mobile phone was hacked by Russian agents while she was foreign secretary.

Mr Spencer said Ms Truss “clearly was hacked” but suggested all ministers used personal phones even if there was “some little man in China” listening in.

“We all talk on personal phones, don’t we, you know? I ring my wife, maybe there’s some little man in China listening to the conversations between me and my wife.

“But, you know, you’ve just got to be careful about what information you use on which phone and you get a lot of help and support from the security services on that.”

Labour will seek to question Ms Braverman about her conduct and issues relating to national security in the Commons, while the Home Secretary is also in the spotlight over conditions at the Manston migrant processing centre in Kent.

Shadow home secretary Yvette Cooper said full details around the breach of the ministerial code which led to Ms Braverman’s initial resignation needed to be set out to MPs.

She told BBC Radio 4’s Today programme: “There is a blunt immediate question, which is how many other security breaches have there been? How many other security lapses has she been involved in? And that’s the most important question.”

Another issue dating to Ms Truss’ chaotic seven-week period in charge could also come back to cause trouble in Tory ranks, with Commons Speaker Sir Lindsay Hoyle expected to receive a report on the stormy scenes in Parliament on the evening before her resignation.

Tory MPs were reportedly manhandled in the voting lobbies as Ms Truss’ administration forced them to oppose a Labour motion on fracking, events which contributed to the collapse in support for the prime minister.