The Scottish government is due to announce its decision on plans to introduce same-sex marriage on Tuesday, following a cabinet meeting in Edinburgh.
The decision comes amid a fierce debate over the proposals to let gay couples marry, with Cardinal Keith O'Brien, Britain's most senior Roman Catholic and an opponent of the move, issuing a last minute demand for a referendum.
Conversely, the pro-same-sex marriage group, the Equality Network campaign, has urged the SNP government to proceed with the plan.
“It is the right thing to do and now is the right time to do it," campaign co-ordinator Tom French said.
“We urge the Scottish Government to stand firm, stick by their principles and make the right decision.
“With cross-party support in Parliament and majority support among the public, it is now time for the Scottish Government to back equality and bring forward equal marriage legislation without delay.”
A Scottish government consultation on the plans received 80,000 responses.
In March, O'Brien controversially compared the introduction of gay marriage to the legalisation of slavery and said countries that had brought in same sex marriage were "violating human rights".
"If marriage can be redefined so that it no longer means a man and a woman but two men or two women, why stop there?" he said.
"Why not allow three men or a woman and two men to constitute a marriage, if they pledge their fidelity to one another?"
Defending his charge that equal marriage was akin to "legalising slavery", O’Brien said: "It is a perfectly good example as to what could happen in our own country if we go this way, It's time to call a halt now to what you may call progress in society."
The Scottish proposals come ahead of a similar move planned by the UK government in Westminster, which has said it will introduce gay marriage by 2015.