David Cameron's new Cabinet is set to meet for the first time after a reshuffle which was widely regarded as marking a shift to the right by the Conservative prime minister.
Cameron has replaced liberal Justice Secretary Kenneth Clarke with hardliner Chris Grayling, and appointed Jeremy Hunt as Health Secretary, with the job of selling the reforms introduced by Andrew Lansley, who has become Leader of the Commons.
Caroline Spelman was sacked as Environment Secretary in favour of Owen Paterson, a right-winger with a much more sceptical approach to subsidies for renewable energy.
Meanwhile, the Prime Minister was accused by London mayor Boris Johnson of plotting to ditch the Government's policy of refusing a third runway at Heathrow, after appointing Patrick McLoughlin Transport Secretary in place of Justine Greening, a vocal opponent of expansion at the airport, who moved to international development.
The changes were welcomed by some of Cameron's backbench Conservative critics on the right of the party, but are likely to dismay many Liberal Democrats.
The five Lib Dem Cabinet ministers all retained their posts, but Business Secretary Vince Cable saw former Conservative co-chairman Michael Fallon installed as a "voice for business" in his department and Chancellor George Osborne's ex-chief of staff Matthew Hancock handed a junior ministerial role.
Further changes to junior posts in the Government were due to be announced on Wednesday, with Cameron expected to appoint members of the 2005 and 2010 intake of MPs as part of a bid to rejuvenate his administration with fresh faces from the back benches.
Among the backbenchers handed ministerial jobs were four women from the 2010 generation - Esther McVey, Helen Grant, Liz Truss and Anna Soubry. Cameron must be hoping that their appointment will help allay criticisms that he is falling behind on his own target of making one-third of his ministers female by the end of this Parliament.
Cameron's spokesman said the shake-up reflected a shift in focus as the Government moves into "the delivery phase" after two years of legislating for reform, adding: "This is a reshuffle that seeks to look to the future and bring in new people into the team and also ensure we have the right ministers in place to deliver the Government's programme."
But Labour dismissed the shake-up as a "no-change reshuffle" which had left the key ministers in charge of economic policy, including Osborne, in post. The new Cabinet will meet after PMQs at 10 Downing Street, where Cameron is expected to demand renewed vigour in the drive to restore growth.