Sajid Javid has said he will not stand again as an MP at the next general election.
In a letter published on Friday, Javid said the decision was one he had “wrestled with for some time”.
The 52-year-old has been the MP for Bromsgrove since 2010 and has held many senior cabinet jobs including chancellor, home secretary and health secretary.
He unsuccessfully stood in the leadership race triggered when Boris Johnson was ousted earlier this year.
Rishi Sunak paid tribute to his “good friend”, with whom he shares a love of Star Wars, by saying: “May the Force be with you, Saj.”
“Sad to see my good friend @sajidjavid stepping back from politics,” the prime minister tweeted.
Javid is the latest Tory MP to announce he will quit rather than fight what looks likely a losing election for the party.
Former work and pensions secretary Chloe Smith has already said she will stand down, as has 29-year-old rising star Dehenna Davison.
Javid said: “Being the local MP and serving in government has been the privilege of my life and I am immensely grateful for the opportunity to serve.
“I always sought to make decisions in the national interest, and in line with my values, and I can only hope my best was sufficient.
“I will of course continue to support my friend the prime minister and the people of Bromsgrove in any way I can.”
His announcement came shortly after the Tories suffered a mid-term defeat in the City of Chester by-election, in Sunak’s first electoral test in the top job.
Keir Starmer hailed the victory for Labour, claiming it demonstrates the public are “fed up” with the current government.
