Former chancellor Kenneth Clarke, who has held office in every Conservative government since 1972, is to resign as a minister.
The veteran MP, who recently celebrated his 74th birthday, was in jovial mood on Monday as he joked with colleagues that he was looking forward to enjoying more time watching his beloved cricket.
Clarke, who first entered parliament in 1970 and secured his first job as a whip in 1972 in Edward Heath's government, is so far the most high-profile minister to leave office in Monday's reshuffle. David Jones, the Wales secretary, has also left the government.
Tory sources have made clear that the prime minister wants the "old lags" to move on to make way for women and younger men. Esther McVey, the employment minister, Liz Truss, the childcare minister, and Nicky Morgan, the women's minister, are all expected to be promoted.
As a highly professional veteran, who stood for the Tory leadership on three occasions between 1997 and 2005, Clarke is understood to have taken the initiative and offered to resign his non-voting cabinet post as minister without portfolio promoting British trade.
Clarke was brought back onto the Tory frontbench at the initiative of George Osborne in early 2009 after the return of Peter Mandelson to the Labour cabinet in 2008. Clarke had sat on the Tory opposition benches between 1997 and 2009.
Clarke shadowed Mandelson as shadow business secretary until the general election in 2010. The coalition, which led to the appointment of Vince Cable as business secretary, led to Clarke's appointment as justice secretary resuming responsibilities for prisons. He had been responsible for them as home secretary between 1992 and 1993.
Lord Howard, the former Tory leader who attended Cambridge university at the same time as Clarke, paid a warm tribute to his former cabinet colleague. Howard, who clashed with Clarke on Europe, told the PM programme on BBC Radio 4: "Ken Clarke has made an extraordinary contribution to our public life; in particular I think he was an absolutely outstanding chancellor of the exchequer. It is therefore quite a moment.
"I have [known him] longer than either of us would care to remember. We were contemporaries at Cambridge over 50 years ago. He always speaks his mind and we have been capable of maintaining a friendship over these years despite the fact that we have quite often disagreed with each other on political issues. That says a great deal about the kind of person he is."
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