The amendments change the wording of the bill so that it clearly identifies the laws as being for same-sex couples only.

It comes as seven Christian, Islamic and Jewish leaders have urged the ACT Legislative Assembly to defer a vote on the marriage equality bill, and send it to a committee for investigation.

The government said on Monday the bill would still be debated on Tuesday and it is expected to pass that day.

The changes to the bill follow talks on Sunday night after the government received legal advice from Australian Marriage Equality.

Interstate MPs and constitutional law experts had raised concerns that the wording of the bill meant there was an additional likelihood it would be struck down when the Abbott government challenges the laws in the High Court.

They said bills to be debated in NSW and Tasmania created a separate status of marriage for same-sex couples and this minimised the risk that those bills would deemed inconsistent with the federal marriage act.

The amendments will give the ACT bill a new title – the Marriage Equality Same-Sex Bill – to make it clear the laws apply to same-sex couples. It was previously titled "The Marriage Equality Bill".

Attorney General Simon Corbell said on Monday the changes would mean the laws no longer applied to people who identified as neither male nor female.

But the government will amend this at a later date if the bill survives the High Court challenge.

“These arguments are very finely balanced and it is not the case these are amendments that are needed to absolutely guarantee the validity of the bill,” Mr Corbell said.

“Quite frankly there’ll be a range of factors that the High Court will look at.

“This changes some issues around the title to clarify scope and ensure that it is very clearly a bill about same-sex marriage.

“Those amendments, the government on balance believes, will help us but they are not central to the arguments we will put to the court.”

Mr Corbell said the government was making the last-minute changes to the laws to give them the greatest chance of survival.

“We are confident and our legal advice is unchanged that the bill is capable of concurrent operation as currently drafted,” he said.

“But we won’t ignore other voices and if there is a most modest of strengthening of our legislation we will take that into account to give it the best possible chance.”

Meanwhile, religious leaders met on Monday to discuss their concerns about same-sex marriage before sending a letter to Assembly Speaker Vicki Dunne.

The leaders included Iman Adama Konda, of the Canberra Islamic Centre; Arnold Cummins, of the Church of Jesus Christ of of Latter Day Saints; Pastor Sean Stanton, of Australian Christian Churches, Canberra; Bishop Treovr Edwards, Vicar General of the Anglican Diocese of Canberra and Goublurn, Pastor BJ Hayes, of the Canberra National Adventist Church; Monsignor John Woods, Administrator of the Catholic Archdiocese of Canberra and Goulburn; and Canberra and region Rabbi Shmuel Feldman.

In a statement, the religious leaders noted that 70 per cent of Australians identified with an Abrahmic religion.

“As leaders of several of these faith traditions, we have gathered to share our concerns about the ACT Government’s proposed same sex marriage legislation,’’ they said.

“We are concerned for the long-term risk of such a bill for our society.

“While affirming the inherent dignity of all human beings, our faith traditions also affirm the traditional concept of marriage between a man and a woman as being for the good of the individual, the family and society.

“We invite the wider community to join for us in calling for the bill to be subject to community consultation through the normal Legislative Assembly Committee process.’’