'Unfair' male right of succession to the throne set to be scrapped

But now ministers want to end the centuries-old male right of succession to the throne under new equality legislation.

In a historic move, the tradition of male primogeniture within the Royal Family is set to be abolished to give a monarch's daughter an equal claim to the throne.

Solicitor General Vera Baird is to steer a new equality law through the Commons, saying the current rules are "unfair" and a "load of rubbish".

In a radical shake-up, she also wants to repeal the law banning the royal heir from marrying a Catholic.

The single equality bill to be drafted later this year, will bring together existing laws on sex discrimination, age, race, disability, sexual orientation and religion.

The Solicitor General told the Sunday Times: "I have always thought that what we have to do with the Royal Family is integrate them as far as possible into the human race."

She added: "The ban on Catholics should be abolished too, because that is discriminatory."

The current law- the 1701 Act of Settlement- was introduced in the reign of William III to safeguard the succession.

Ill and childless at the time, his sister-in-law Anne had just lost her only child and with no heir it was feared that the succession would fall to the deposed Roman Catholic James II or his offspring.

The Act provided that the Electress Sophia of Hanover- a Protestant granddaughter of James I - would succeed and Roman Catholics were barred for ascending to the throne" for ever".

But in the event, Sophia died before Anne so Sophia's son, George I was crowned.

The Act enshrined male primogeniture in law, which for centuries had been an unwritten rule dating back to the notion that a feudal monarch would lead troops into battle.

Today it is regarded as one of the most significant statutes in English history, acting as a precursor to the Act of Union which established the Kingdom of Great Britain.

The course of Britain's history could have been very different if the eldest royal daughters had been allowed to inherit the throne.

Historians have speculated that Britain might not have gone to war with the Germans in 1914.

Queen Victoria would have been followed not by Edward VII, but by Victoria, her eldest daughter.

She was the mother of the Kaiser Wilhelm II, the German Emperor blamed for starting the war, who could, in turn, have also occupied the British throne.

And without the tradition of primogeniture, there might not have been a Civil War in 1688.

Instead of Charles I, whose reign ended in the war and his execution, his elder sister Elizabeth would have succeeded.

Today, a change in law would not change the current line of succession.

But if Prince William's oldest child was a girl and he also had a younger son, his daughter would become Queen.

The move would bring the Royal Family into line with those of the Belgian, Dutch and Swedish monarchies who changed their similar rules on the male succession in the early 1990s.

Trevor Philips, chairman of the Equality and Human Rights Commission, has signalled his support for reform in a letter to Lynne Featherstone, the Liberal Democrat equality spokeswoman.

She said: "We can't have a law that is meant to fight government discrimination and injustice and allow a blatantly sexist law on royal succession to continue.

"This is the perfect time to do this when there is no one who will be personally affected. It shouldn't create a hue and cry."

But critics have pointed out that it will be difficult to change the law.

Labour MP Andrew Mackinlay, who has raised the issue with successive prime ministers, has welcomed the move.

But he said Ms Baird was "naive" if she thought Westminster could act on its own to change the rules, as under the Statute of Westminster 1931 any change would have to be agreed by the parliaments in all countries which have the Queen as head of state.