Ben Wallace – the longest-serving Conservative defence secretary – is considering leaving government in an anticipated autumn reshuffle, Sky News understands.
It follows a failed UK bid to make Mr Wallace, 53, the next head of NATO and as the prime minister reportedly prepares to refresh his top team ahead of next year’s election.
The possible departure of the defence secretary – a close ally of former prime minister Boris Johnson – was first revealed by The Times.
A source told Sky News that Mr Wallace would likely make a decision on whether to stay or go next month. If he chooses to leave then he would also stand down as an MP.
It is thought that any such move would be a personal decision and nothing to do with Rishi Sunak or any issues related to the Conservative Party.
Speculation about the defence secretary’s fate has been mounting for weeks, with officials inside the Ministry of Defence wondering who might replace him.
Anne-Marie Trevelyan, a foreign office minister and former defence minister, Tom Tugendhat, the security minister, and Jeremy Quinn, a cabinet office minister who is also a former defence minister, are among the names being speculated on.
“Not sure who will replace (him) but Jeremy Quinn a strong possibility,” one source said.
The Times said John Glen, chief secretary to the Treasury, was the frontrunner.
Hugely popular within the party, Mr Wallace is the longest, continuously-serving minister in government, having survived five prime ministers since 2014, including as security minister and then – for the past four years – overseeing the Ministry of Defence.
In his current role, he has been a leading voice pushing the UK and its allies to do ever more to support Ukraine.
Mr Wallace is also known for speaking his mind and using colourful language that has on occasion generated unfortunate headlines.
It happened at a major NATO summit this week when he revealed to a group of journalists that he had told Ukraine the UK was not an “Amazon” delivery service for weapons and that people “want to see gratitude”.
It prompted Volodymyr Zelenskyy, the Ukrainian president, to say in a press conference at the summit in Lithuania: “I believe that we were always grateful to the UK.”
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Zelenskyy has ‘expressed gratitude’, Sunak says
Mr Zelenskyy then, rather comically, asked his defence minister, Oleksiy Reznikov, who was sitting in the audience, whether there was a problem with his relationship with Mr Wallace.
“Why don’t you extend words of gratitude to him?” the president said. Breaking into English, he added: “Call him, please, today.”
Yet, the point Mr Wallace had been trying to make had been a valid one – a bit of friendly advice to a country he respects about the need to consider the political reality in certain nations where not everyone is supportive of giving more weapons and money to Ukraine.
The defence secretary has spent much of his time in office battling for more funding for the armed forces at a time of growing threats and after decades of cost-saving cuts.
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This has on occasion created tensions with Mr Sunak, first when he was chancellor and then as prime minister.
The two men are not known to have a close relationship but the strong support for Mr Wallace within the Conservative Party will make him difficult to sack.
The defence secretary turned down the chance to run for prime minister last year even though he had been the clear favourite to replace Mr Johnson.
Another consideration for Mr Wallace is the fact that he will effectively lose his constituency of Wyre and Preston North at the general election under boundary changes.
It means, to stay on as an MP, he would need to become the Tory candidate in another seat – which could be done should he choose to stay.