Ms Leadsom was one of two of those who challenged Mr Johnson for the leadership last summer to lose their jobs, as Esther McVey was removed as housing minister.
After being dismissed in a meeting in the prime minister’s Commons office, Leadsom said: “It has been a real privilege to serve in government for the last six years, and in the Department for Business, Energy and Industrial Strategy for six months.
“I now look forward to focusing on my constituents and on my 20+ year campaign to see every baby get the best start in life.
“I’m particularly proud of my work in BEIS on net zero and the countdown to the COP (climate change summit) and on making the UK the best place in the world to work and to grow a business. I will continue from the back benches to work to ensure everyone is treated with dignity and respect.”
MP for South Northamptonshire since 2010, Ms Leadsom served in the Treasury and as energy minister under David Cameron and joined Theresa May’s cabinet as environment secretary and later leader of the Commons.
She reached the final two in the battle to replace Mr Cameron as leader in 2016, but pulled out before the final vote after making controversial comments about the importance of the PM being a parent, leaving the route clear for Ms May to take the top job unopposed.
Her second tilt at the leadership came after Ms May’s resignation in July last year, when she was eliminated in the first round with just 11 MPs’ votes in the contest which Mr Johnson went on to win. Ms McVey came last in the same contest with nine votes.
Announcing her dismissal on Twitter, Ms McVey said: “I’m very sorry to be relieved of my duties as housing minister I wish my successor the very best and every success.
“I’m very grateful to the prime minister for having given me the opportunity to serve in his government and he will continue to have my support from the back benches.”
Also losing their jobs in the reshuffle were Northern Ireland secretary Julian Smith and environment secretary Theresa Villiers.
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