The call by Cardinal Keith O’Brien, head of the Catholic Church in Scotland and the most senior Catholic in the UK, for a referendum on equal marriage rights for gay couples has been criticised by advocates of the move.

The Equality Network said support in opinion polls indicated the Scottish public would likely support equal marriage rights for gay and straight couples in such a vote, but said the cardinals argument was “not the way Scottish democracy works”.

Cardinal O’Brien, who has previously described the idea of equal marriage rights as a “grotesque subversion of a universally accepted human right”, said the matter should be put to a public ballot.

Today, he argued in the Scotsman: “The concern for those who demand equality cannot allow us to consign to history our understanding of the basic goods of human society.”

Comparing it to the planned referendum on whether Scotland should become independent from the rest of the UK, he added: “Clearly, if it is sensible to hold a referendum on independence, it is crucial that we have one on marriage. It is the only way the country can move forward on this issue.

“Let all those who have a view on this subject place their trust in the Scottish people and let Scotland decide.”

A Scottish government spokeswoman said: “The cabinet have had a first discussion on the next steps following the consultation on same sex marriage and the registration of civil partnerships and have asked for some further detail.

“We fully expect to be in a position to publish the way ahead this month.”

The Equality Network has said in response that MSPs were elected with promises to consider whether gay should be allowed to marry and to come to a decision on behalf of the Scottish people.

Tom French, Policy Coordinator for the Equality Network, said: “If there was a nationwide referendum, conducted fairly, we are sure that Scots would vote for equality for same-sex couples. But that is not the way Scottish democracy works.

“Our MSPs were elected on clear manifesto commitments to consider the evidence, and decide, and we have confidence in them to do that. A referendum would be un-Scottish, unfair and a colossal waste of taxpayer’s money.”

He added: “We urge the Scottish Government to stand firm, stick by its principles and make the right decision. With cross-party support in Parliament, and majority support amongst the public, it is now time for the Scottish Government to back equality and bring forward equal marriage legislation without delay. It is the right thing to do, and now is the right time to do it.”

The Catholic Church recently announced it will spend an additional £100,000 on an advertising campaign against the plans, on top of the £50,000 it has already spent against marriage equality in Scotland.