Moves to end the 300-year-long ban on Roman Catholics taking the throne and on eldest daughters succeeding as monarch are being seriously considered by Downing Street, it was reported today.
The Guardian said the constitutional reforms were included in proposals drawn up for Prime Minister Gordon Brown by Labour MP Chris Bryant.
Legislation including the 1701 Act of Settlement bars all Catholics and anyone married to a Catholic from reigning and forces any monarch coming to the throne to reject Catholicism.
A Downing Street spokesman said the Government was "always ready to consider the arguments" surrounding the issue.
But the Prime Minister is not believed to have been personally involved in the process and it is not Government policy.
"To bring about changes to the law on succession would be a complex undertaking involving amendment or repeal of a number of items of related legislation, as well as requiring the consent of legislatures of member nations of the Commonwealth," the spokesman said.
"As the Secretary of State for Justice said in the Commons on March 25, we are of course aware of the concerns felt by many and we are always ready to consider the arguments in this complex area."
Mr Bryant confirmed that he had submitted his proposals to No 10 but would not be drawn on their contents.
In a pamphlet published last week by the Local Government Association, he argued that forcing the monarch to swear to preserve the Church of England and uphold the Protestant line of succession almost certainly represented a breach of human rights.
And he suggested it was "inconceivable" that, should Prince William have a daughter before a son, she would not be the one to eventually take the throne.
Sweden, he pointed out, has already changed its law to deal with such a situation.
The MP, a former priest, also argued for reform of the constitutional role of the Church of England and of the "strange" powers of the Privy Council.
A future coronation would have to be "radically different" from that of the present Queen's, he suggested, "to recognise the monarch's role in protecting the freedoms of all citizens and subjects, rather than just the Church of England".
Liberal Democrat equalities spokeswoman Lynne Featherstone said: "This is an overdue but welcome move.
"Whilst the hereditary principle itself is obviously still a bit dodgy, at least this modernisation ends the outrageous discrimination against Catholics and women.
"As I pointed out earlier this year, it was completely unfair that Prince Edward's daughter was bumped down the list of succession in favour of her younger brother.
"We shouldn't kid ourselves that this change will make the difference for the millions of women who face lower wages and unfair conditions in their day to day lives.
"But, as we chip away at the established order, the message will eventually get through that men and women are equal.
"We can also put to bed centuries-old bigotry towards Catholics that has no place in our multi-faith society.
"I therefore hope the change will extend to royal spouses of all religions."