On 28 October 2011 , at the Commonwealth Heads of Government Meeting held in Perth , Western Australia , the heads of government of the 16 Commonwealth realms , which share Elizabeth II as head of state , announced that they would introduce legislation in all 16 countries to end the primacy of males over females and the disqualification of persons married to Catholic spouses in the succession to the Crown . In a letter to the other realms ' heads of government , prior to the Perth Agreement , British Prime Minister David Cameron additionally proposed to limit the requirement to obtain the monarch 's permission to marry to the first six people in line to the throne
Commonwealth Heads of Government Meeting
Commonwealth Heads of Government Meeting 2011
Royal Succession Act 2013