Legislation in the 15 Commonwealth countries where the Queen is head of state would also need amending.

BBC: Review could see Prince William's daughter as Queen

It came after consent was given by all 15 Commonwealth realms to press ahead with the legislation and will be voted on in the Commons as soon as parliamentary time allows.

BBC: Royal baby girl 'would be princess'

The legislation was agreed in principle at the Commonwealth heads of government meeting in Perth, Australia in October 2011.

BBC: Royal succession bill published