(Roger Lockyer (L) and Percy Stephens pose for photographers, after or their civil partnership ceremony, at Westminster Town Hall in central London December 21, 2005/Paul Hackett)

Britain outlined plans on Tuesday to allow gay marriage that have split Prime Minister David Cameron’s Conservatives and raised fears among religious groups they will be forced to hold same-sex weddings.

Gay couples may already have “civil partnerships”, conferring the same legal rights as marriage, but campaigners say the distinction gives the impression that society considers gay relationships inferior.

Cameron has stressed he is a strong backer of gay marriage but does not plan to force his party’s members of parliament to vote in favor of legislation, which will apply to England and Wales and be introduced by the end of the current parliament in 2015. Scotland has separate plans for same-sex marriage.

Opponents of the measure include the Church of England and several members of Cameron’s own party.