Britain said on Saturday it was mulling changes to "discriminatory" rules on the line of succession, meaning Prince William and Kate Middleton's first born could accede to the throne regardless of gender.
Currently the principle of male primogeniture means that the first born son would be next in line to the throne, even if he had an older sister.
But Deputy Prime Minister Nick Clegg, who is responsible for constitutional reform, is looking at ways of changing the rule to grant any future princesses born to the couple the same rights as male heirs.
William, the second-in-line to the British throne, will marry Kate at London's Westminster Abbey on April 29.
The British monarch is head of state of 16 Commonwealth nations and any change to the line of succession would require legislation in all these countries.
A government spokesman said discussions had started with Commonwealth countries that would be affected.
"Amending the laws regarding succession to the throne is a complex and difficult matter that requires careful and thoughtful consideration," said the spokesman.
"The government accepts there are provisions which could be discriminatory. "Discussions have started with those Commonwealth countries who would be directly affected by any change in the rules, and are continuing, but it would not be appropriate to release details at this stage."
Kate and Harry rehearse for royal wedding
Keen to make sure her wedding to Prince William passes off smoothly, Kate Middleton took part in a rehearsal on Friday with her maid of honour and the best man, Prince Harry, at Westminster Abbey.
Kate, William's younger brother Harry and her younger sister Pippa were joined by the young bridesmaids and page boys who will accompany the bride down the aisle on April 29, to ensure they know what to do on the big day.
William himself could not take part because he was working at the Royal Air Force base on Anglesey where he is a search and rescue pilot.
"This was one of many rehearsals that will take place and is not the first," the prince's spokesman said.
The abbey was closed to tourists for the rehearsal, which was reportedly aimed at ensuring that Kate's young entourage - the youngest bridesmaid is just three years old - are not too overwhelmed by the grandeur of the place.
Palace officials released a detailed timetable of the wedding Friday, and confirmed that Kate will spend her last night as a single woman with her family at the Goring Hotel, not far from Buckingham Palace.