Autumn Kelly gave up her Catholic faith before marrying Peter Phillips
A fresh attempt is to be made to reform a 308-year-old law which bars the monarch from marrying a Catholic.
Liberal Democrat MP Evan Harris will present a bill to parliament in a bid to change the Act of Settlement.
He also wants to end the discrimination against female heirs to the throne, but his bill does not alter the requirement for the monarch to be a Protestant.
There have already been several bids to reform the law on the grounds it is outdated and discriminatory.
The 1701 Act of Settlement states that only the Protestant heirs of Sophia, granddaughter of James I, can become King or Queen.
It was drawn up to ensure the Protestant succession in more religiously turbulent times.
The Act means Catholics or those who marry a Catholic cannot become sovereign and it also gives legal precedence to male heirs in the line of succession.
Autumn Kelly, wife of the Queen's grandson Peter Phillips, gave up her Catholic faith ahead of their 2008 wedding so her husband could retain his right to the throne. He is currently 11th in line to the throne.
Prince Michael of Kent, the Queen's first cousin, is among a small number of royals who have renounced their place in the line of succession by marrying a Catholic.
Of these, George Windsor, Earl of St Andrews and a second cousin of Prince Charles, would be the highest in the line of succession.
The Act has been challenged over the years as being incompatible with principles enshrined in European law.
BBC political correspondent Norman Smith said previous attempts at reform had failed largely because of fears about the impact on the Church of England as the established church.
Dr Harris hopes his bill will gain government support as it proposes more limited reform.
"It is wrong that anti-Catholic discrimination is written into the UK's constitution," he said.
Last year, Jack Straw, who as Justice Secretary is responsible for constitutional matters, said the government was "ready to consider" changing the law.