The Queen will honour Baroness Thatcher, her longest serving prime minister, and attend the funeral of the woman who changed the face of modern British politics.

She will take her seat in St Paul's Cathedral with the Duke of Edinburgh by her side as the nation pays tribute to the major political figure next Wednesday.

It will be the first time the Queen has attended the funeral service of a former prime minister since Sir Winston Churchill's state ceremony in 1965.

Baroness Thatcher and the Queen had a working relationship that lasted more than 10 years, but it was a partnership described as "more businesslike than warm".

Mrs Thatcher was the eighth prime minister and first woman the Queen summoned to take up office during her reign.

As Britain's leader for 11 years, she was granted weekly audiences with the head of state, when Parliament was sitting, when the two women could speak frankly about the issues of the day.

Some commentators have raised questions about the relationship between the Queen and Mrs Thatcher.

Author and journalist Anthony Sampson wrote in 1982: "The relationship is the more difficult because their roles seem confused. The Queen's style is more matter-of-fact and domestic while it is Mrs Thatcher (who is taller) who bears herself like a queen."

Ben Pimlott in his biography of the monarch, called The Queen, quotes an unnamed source as describing the relationship as "more businesslike than warm".

The biographer also quoted an un-named ex-minister who was close to Thatcher in her early years: "She was affected by the aura, the trappings but she was slightly nervous. I think she was in awe of the position."

Mrs Thatcher also reportedly found her annual September trip to the Queen's private Balmoral estate in Scotland a painful experience at the start of her premiership.

One observer wrote: "A weekend in the country with aristocrats who enjoy riding, shooting, sports and games is Thatcher's idea of torture. But her dread of the weekend receded as the two women became somewhat more comfortable with one another."

Mrs Thatcher was not a fan of the game of charades she was expected to play after dinner at Balmoral, and once during a gathering of six of her Premiers, the Queen joked about "the party games which some of you have so nobly endured at Balmoral".