New Zealand’s equal marriage bill is to be heard for the first time today in parliament, and various lobby groups and a number of MPs will also be declaring their opposition to it.

There are currently 64 MPs who are backing the amendment to the country’s marriage legislation; 61 votes are required for it to progress to a select committee.

Labour MP and sponsor of the bill Louisa Wall made a late appeal to opposing and undecided MPs yesterday, saying the present law discriminated against same-sex and transgender couples.

Ms Wall said: “[A marriage licence] is the only licence you can’t get if you’re homosexual in New Zealand. I feel it’s wrong and we need to make sure that we live in a just and equal society.”

But three members of her caucus remain staunch in opposition: Ross Robertson, Su’a William Sio and Damien O’Connor have all pledged to vote “no”.

As reported in the New Zealand Herald, the former two were among the MPs yesterday who met with the conservative lobby group Family First outside Parliament to accept a petition – with 48,000 signatures – asking the bill be scrapped.

Act Party leader John Banks said he would vote for the bill at the first reading, having previously voted against Homosexual Law Reform and the Civil Union Bill. Asked about his change of heart and why he was now supporting it he simply said: “Because I am.”

Many MPs have pledged their support to the first reading only, and their ongoing support depended on the debate at select committee.

Among their worries were how the change in law would affect adoption rules and access to reproductive technology.

National MP Paul Hutchison, who opposed the bill, said: “We’re in a situation where a gay individual can adopt, [and] a gay couple cannot adopt. We haven’t even talked about that kind of stuff and I think it’s very important that we do.”

Ms Wall said she hoped the debate would remain honest and in reference to a legal opinion from Family First which said church ministers and celebrants who refused to marry gay couples would be criminalised by the bill, added: “I don’t like scaremongering and the fact that ministers are saying [they] will have to go to jail.

“They will retain all the rights that they currently have . . . my bill isn’t going to affect them in any way.”

In advance of the bill, thousands marched through the city of Wellington in support.

Campaign for Marriage Equality arranged the march, which arrived at parliament at 1pm local time, with supporters holding placards saying ”all love is equal”, and traffic being stopped to allow the column through.

Joseph Habgood, of LegaliseLove Wellington, one of the groups involved in organising the event, said:

”It’s a lot of work for campaigners and it’s still a struggle, but it’s a good time to show how far we’ve come [as a country]. It’s a show of happiness that this is actually happening,” reports Stuff.nz:

”It’s not something that I think should be controversial. It’s something to get behind … It’s a huge excitement.”