Mr. Wallace's departure, which had been announced last month, was confirmed through an exchange of letters with the Prime Minister.

Grant Shapps, the Net Zero Secretary, appears to have been selected for the pivotal role, necessitating broader changes within the Cabinet.

Mr. Shapps, who entered No10 with a broad grin this morning, has held various roles throughout his political career, although never a defence-related position.

Armed Forces Minister James Heappey and Chief Secretary to the Treasury John Glen were both speculated to be contenders for the role.

However, there was also talk of an unexpected choice, with former Defence Secretary Liam Fox being mentioned among the possible candidates.

Rishi Sunak is preparing for a minor reshuffle today following Ben Wallace's formal resignation as Defence Secretary. +4 View gallery Rishi Sunak is preparing for a minor reshuffle today following Ben Wallace's formal resignation as Defence Secretary.

Mr. Wallace's departure, announced the previous month, was confirmed through an exchange of letters with the PM. +4 View gallery Mr. Wallace's departure, announced the previous month, was confirmed through an exchange of letters with the PM.

Dr. Fox, who served in the role under Prime Minister David Cameron between 2010 and 2011, was compelled to step down after allowing his friend and best man, Adam Werritty, to assume an unofficial and undisclosed advisory role.

The prominent Tory MP supported Mr. Sunak in the Conservative leadership race last summer.

Mr. Wallace, who held his current role under three prime ministers, received praise for overseeing the UK's response to Russia's invasion of Ukraine and enjoyed a close alliance with Boris Johnson.

A favorite among Tory members, he was once considered a potential leadership contender.

However, he withdrew from the race for Conservative leadership last year, despite being an early frontrunner in the campaign to succeed Mr. Johnson.

Earlier this summer, Mr. Wallace was also in the running to become the head of NATO, but his bid was thwarted due to opposition from Joe Biden and France, who insisted that the next chief should hail from an EU state.

Shortly thereafter, Mr. Wallace announced his intention to step down from the Commons at the next election, following a controversy stemming from his suggestion that Ukraine should show more 'gratitude' for Nato support. Photo by Chris McAndrew, Wikimedia commons.