William Hague surprised Westminster on Monday evening by announcing he would quit as foreign secretary, as David Cameron culled male ministers of all ranks as part of a wide-ranging reshuffle expected to see the promotion of several women to top jobs.
Hague will replace Andrew Lansley as leader of the House of Commons until 2015 - when he will step down from parliament.
Defence secretary Philip Hammond is expected to become the new foreign secretary. He would take over as Cameron looks to begin negotiating for Britain a looser relationship with the EU ahead of an in/out referendum in 2017. Hammond has previously said he would vote to leave the union if a referendum were held today as Brussels holds too many powers.
Hague was first elected in 1989 and served as Welsh secretary under John Major before succeeding him as Conservative Party leader in 1997. He stood down as leader in 2001 after losing the general election to Labour and Tony Blair, but was persuaded to return to frontline politics in 2005 when Cameron took over the party.
The Richmond MP said on the role as leader of the Commons meant he would "finish in politics as I began – speaking in Parliament and campaigning among the voters".
"From May 2015, after such a long period in politics I want to embark on many other things I have always wanted to do. Renewal in politics is good, and holding office is not an end in itself. After 26 years as an MP time will be right for me to move on," he said.
The prime minister said Hague would continue to play a key role in the Conservative Party's election campaign as his "de facto political deputy".
"William Hague has been one of the leading lights of the Conservative Party for a generation, leading the party and serving in two cabinets," Cameron said.
"Not only has he been a first class foreign secretary - he has also been a close confidante, a wise counsellor and a great friend. He will remain as first secretary of state and my de facto political deputy in the run-up to the election - and it is great to know that he will be a core part of the team working to ensure an outright Conservative victory at the next election."
Veteran cabinet minister Ken Clarke has also stepped down from the government as expected. Other big names given the chop, or who have resigned, include environment secretary Owen Paterson, Attorney General Dominic Grieve, Wales secretary David Jones and chief whip Sir George Young.
The reshuffle, which got underway early on Monday evening, has been very bad for middle aged white men elected before 2010. Development minister Alan Duncan, universities minister David Willetts, energy minister Greg Barker and police minister Damian Green are all leaving their Whitehall offices.
The prime minister is expected to promote several female MPs into his top team in order to combat accusations that he ignores women.
Those tipped for advancement include employment minister Esther McVey - who was also seen entering No 10 - education minister Liz Truss and ministerial aide Penny Mordaunt. Other MPs tipped for promotion include Margot James, Amber Rudd and Harriett Baldwin, as the Tory leader seeks to counter criticism that his government is still dominated by men.
Former defence secretary Liam Fox, a darling of the Tory right, could make a comeback to the political front line nearly three years after quitting in a row over his special adviser.
The Labour Party seized on the number of modernising Tories who had lost their jobs as evidence that Cameron was lurching to the right. Attack dog shadow cabinet minister Michael Dugher said it was a "massacre of the moderates".
“Britain's foreign policy is now set to be led by a man who has talked about taking us out of the EU. The Tories are now retreating out of Europe with all the threat that poses to jobs and business in Britain," he said. "This reshuffle shows how weak David Cameron is, running scared of his own right wing."
Lib Dem Jeremy Browne, who served under Hague as a coalition Foreign Office minister, paid tribute to his former boss. "I greatly admired William Hague as foreign secretary. Much respected internationally; also a calmly disciplined and professional politician," he said.
But Browne had harsher words for Hague's successor. "Philip Hammond as foreign secretary. Seriously? Quibbling over micro detail of EU communiques: tick. A big global vision for Britain: errr," he said.
Hague departs the Foreign Office amid a series of international crises, including the civil-war in Syria, the rise of extremist forces in Iraq and the recent explosion of violence between the Israelis and the Palestinians.