Plans to allow heterosexual couples to be allowed to have civil partnerships in Scotland are expected to be unveiled next week as part of a review.

The proposal will not be included in the forthcoming Marriage and Civil Partnership (Scotland) Bill, which is set to be introduced in the Scottish Parliament before the start of the summer recess on Saturday 29 June.

Instead the aim is for a review on civil partnerships to take place over the next year or so, with the prospect of legislation after that.

In the same way as in England and Wales, civil partnerships in Scotland are currently restricted to same-sex couples only.

Scotland’s Equality Network, which has campaigned in favour of same-sex marriage and straight civil partnerships, said opening up the idea of civil partnerships to all was widely supported.

Tom French said: “Opening up civil partnership to mixed-sex couples has always been a key aim of the equal marriage campaign in Scotland and is supported by the majority of Scots.

“The Equality Network believes the law should be equal with the same choices for everyone. We hope the Scottish Government will set out a clear path to changing the law in this area.”

Equality Network found in a poll last year that 71% backed the idea of straight civil partnerships, compared to 64% for same-sex marriage.

However, a spokesman for Scotland for Marriage, which is opposed to marriage rights for same-sex couples, said: “This won’t redefine marriage; it will wreck it. It will introduce a marriage-lite alternative for straight couples who don’t want to get hitched, giving them all of the rights of marriage with none of the matrimonial responsibilities.”

He added: “The Westminster pensions minister looked into extending civil partnerships to straight couples in England, and said it will cost the taxpayer £4 billion in public pension rights alone.”

Last week, the UK Government announced its intention to launch a full-scale public consultation and review on civil partnerships in England and Wales.

It will run for approximately twelve weeks and start in the autumn.

In light of pending equal marriage legislation some MPs would like to see future civil partnerships phased out – others believe they should be extended to heterosexual couples.