The British government is drawing up plans to end a 300-year-old exclusion of Catholics from the line of succession, as well as ending the priority given to male heirs, a newspaper reported on Thursday.
The Labour government would introduce the necessary legislation after the next election, according to The Guardian, which has long petitioned for a change in the law that critics have condemned as discriminatory.
Prime Minister Gordon Brown's office declined to comment, although Justice Minister Jack Straw said in March that the government was "certainly ready to consider" reviewing the "antiquated" ban on Catholic monarchs.
Rules laid out in the Bill of Rights 1688, the Act of Settlement 1700 and the Act of Union 1706 state that the monarch must be a Protestant, and any royal who marries a Catholic is barred from the line of succession.
Earlier this year, a Catholic engaged to one of the Queen's grand-children, Peter Phillips, had to be accepted into the Church of England before the couple could marry, or her husband would have lost his claim to the throne.
Changes to the rule stating that the crown automatically passes to the first male heir were also planned, The Guardian said, and could see a first-born daughter of Prince William, second in line to the throne, become queen.
Former prime minister Tony Blair said in 1999 he had no plans to change the law, mainly because it would require amending several pieces of legislation and would have to be approved by the Commonwealth nations.
A parliamentary briefing paper published in August warned that changing the law "could open up extremely complex constitutional issues".