BARONESS Thatcher has invited only two of the five Conservative Party leadership candidates to her 80th birthday party this week, in the clearest indication of who she wants to succeed Michael Howard.

David Davis and Liam Fox, the flag-bearers of the Tory right, will join the Queen, the Duke of Edinburgh and 650 other guests on Thursday at the Mandarin Oriental Hotel in Hyde Park to celebrate this milestone for Britain’s first woman Prime Minister. But there is no invitation for David Cameron, the new bookmakers’ favourite for the leadership, who never mentioned Lady Thatcher in his conference speech, or Kenneth Clarke and Sir Malcolm Rifkind, who both served in her Cabinet.

Appearance at the party will provide an opportunity to cement leadership credentials before the MPs’ first vote on October 18. The final two candidates will be voted on by 300,000 Tory members, with the result declared on December 6.

Lady Thatcher, who endorsed William Hague in 1997 and Iain Duncan Smith in 2001, has no plans publicly to support anyone this time.

But the absence of Mr Cameron, whom she does not know, and Mr Clarke, who was her Health Secretary, and Sir Malcolm, who was her Scottish Secretary, will be interpreted as a signal from the Thatcher camp.

Lady Thatcher, who made her peace in the summer with Sir John Major, who complained that she had undermined his premiership, has now buried the hatchet with Lord Howe of Aberavon, the former Chancellor, whose resignation speech triggered the events that led to her downfall. Lord Howe and his wife, Elspeth, will be at her party.

Lord Lawson of Blaby, who resigned as Lady Thatcher’s Chancellor in 1989, will join Lady Thatcher alongside Lord Tebbit, Lord Parkinson and Lord Baker who was Tory chairman when she resigned from office in November 1990.

Lord Archer of Weston- super-Mare, the best-selling novelist, and his wife, Mary, will also be there. Lady Thatcher has maintained her friendship with Lord Archer despite his prison spell for perjury. Her three successors as leader, Mr Hague, Mr Duncan Smith and Michael Howard, will all attend with their wives.

“Virtually all the Cabinet who served her will be at the party,” said an aide.

While she remains a hate figure on the Labour left Tony Blair, who consulted her early in his Downing Street tenure, will attend with his wife, Cherie, who may find the tribute speeches to Lady Thatcher a little uncomfortable.

Her children, Carole and Mark, will attend but, sadly for Lady Thatcher, Mark’s estranged wife, Diane, and their two children will be in America. Sir John Major was invited but will be out of the country on Thursday, which is the day that nominations close for the Tory leadership.

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