In March 2002 doctors ordered her to "take things easy" following a series of small strokes.

And although she has made public appearances since, they have become less frequent.

In the past her appearances at party conferences had a tendency to over-shadow successive Tory leaders from John Major to William Hague.

Entering Downing Street as Prime Minister, May 1979

But idealogically she remains a huge presence in the party and many members hark back to the halcyon days of Tory power, which those who came after her have failed to recreate.

Bitter struggle

The former premier is said to be still mourning her husband who died in June 2003.

He was there when she first walked into 10 Downing Street as prime minister in 1979.

And he was there when - to the surprise of many commentators - she shed a tear on leaving it 11 years later.

An internal power struggle within the party had finally pushed her off her top perch but it was only after a decade in British history she had made her own.

The Thatchers at Chequers

She threw herself into making Britain competitive and old style manufacturing was hit hard.

As unemployment rose above three million in the early eighties, she became one of the most unpopular prime ministers in history.

That was all to change with the Falklands War in 1982, when she copper-plated her iron lady image.

But more conflict was to come as she faced down the miners in their bitter 1984 dispute.

Political presence

Just three years later, her introduction of the poll tax or community charge saw some of the worst street violence in living memory.

But it was thorny subject of Europe which was to be her downfall.

Her intransigence over Britain's involvement in the EU led to bitter disagreements with Cabinet colleagues.

Michael Heseltine challenged her for the leadership and close political friends told her she would lose.

After her humiliating resignation, it could have been the end of public life for her, but she was never far politics whether it was through her presence in the House of Lords or through her speeches on the after-dinner circuit.

The Iron Lady's steel remained undiminished and but for her health she would have probably continued to assert herself whenever she felt sufficiently roused.