The former Archbishop of Canterbury, Lord Carey, is seeking to wreck the equal marriage bill for England and Wales, by tabling an amendment suggesting that there be two “tiers” of marriage.

Lord Carey has tabled an amendment which could potentially undermine the Marriage (Same Sex Couples) Bill, by redefining opposite-sex marriage as “traditional” marriage, and calling for a distinction to be made between opposite-sex and same-sex marriages.

The proposed clause would read that “nothing in this Act could take away the right of a man and woman to enter a traditional marriage”.

It continues: “A ‘traditional marriage’ is one where the basis of the marriage is the voluntary union of one man and one woman for life, to the exclusion of all others.”

The amendment does not suggest a label for same-sex couples.

The bill survived its second reading last week, as an amendment tabled by Lord Dear was rejected by 390 votes to 148.

The bill comes back in committee the week commencing 17 June. It will have its report stage on 8 July and third reading on 15 July. Ministers are hoping that the bill will have Royal Assent before summer recess, at the end of July.

Equal marriage critic Lord Dear has proposed another, similar amendment to the Marriage (Same Sex Couples Bill), protecting those who believe marriage is “the union of one man and one woman for life to the exclusion of all others.”

Earlier in June, Lord Carey, argued that marriage equality should be opposed on the grounds that allowing marriages based “merely” on love and commitment would also justify polygamous unions and weddings between siblings.

In an essay titled ‘Love is Not Enough’, published by the think tank Civitas, Lord Carey argued “not all relationships are the same”.

He put forward claims that marriage equality would enable incestuous marriages to take place – an argument recently given publicity by Lord Norman Tebbit, when he asked of same-sex marriage in an interview: “Why shouldn’t a mother marry her daughter? Why shouldn’t two elderly sisters living together marry each other? I quite fancy my brother!”

Lord Carey, has previously accused David Cameron of creating a “broken society” through the same-sex marriage bill.

Out4Marriage has launched the LobbyALord website in order to make it easy for members of the public to lobby Peers on the issue.