The Greens are open to negotiating with the federal government on its help to buy policy, despite the party's housing spokesman saying it "screws over the vast majority".
Under the program, the government would contribute up to 40 per cent of the value of a home for a new property or 30 per cent for an existing one for a first home buyer as part of a shared equity scheme.
Home buyers would then be able to contribute as little as two per cent for a deposit.
But Greens housing spokesman Max Chandler-Mather said the program would do little to ease the strain on the housing market or get people to buy their first home.
"The government scheme would only help 0.2 per cent of renters buy a home every year and for the other 99.8 per cent of renters in this country, it will actually drive up prices," he told ABC's Insiders program on Sunday.
"It screws over the vast majority of people, and frankly, I don't think Australians should have to win this bizarre lottery, where you've got just a 0.2 per cent chance of winning, just to get an affordable home."
The government needs the support of the Greens for the scheme to get through parliament.
While Mr Chandler-Mather expressed criticism of help to buy, he conceded the party was still up for talks on the issue.
"There'll be a broad net-positive if we can negotiate a phase out of tax handouts to property investors, get a cap on rent increases and build public housing," he said.
"If we have to negotiate with the government to get through their little scheme, that will have an inflationary impact on house prices, but on the other hand we can get through the changes to capital gains, tax concession and negative gearing, then overall that would be a good thing."
Prime Minister Anthony Albanese said the legislation would still be before parliament, regardless of the position of the Greens.
"If they vote against it, they'll be voting against helping Australians into home ownership, it's as simple as that," he told reporters in Nowra.
"The key to dealing with housing is supply, the Greens have no answer on supply. We're working on a comprehensive plan."
Ahead of the 22 federal election, the Greens had called for negative gearing to be grandfathered out, with the arrangement being phased out over five years and people only allowed to apply the measure to one investment property.
The government has come under pressure to examine negative gearing following its policy reversal on changes to stage three tax cuts.
Mr Chandler-Mather said a removal of negative gearing may lead to a reduction in rental prices.
"There may actually be downward pressure on rents because one of the things these tax handouts in combination have done, including the capital gains discount, is deprive a lot of renters the chance to buy a home," he said.
"If those changes hadn't happened, we'd have an extra 400,000 renters who could have bought a home."
Agriculture Minister Murray Watt urged the Greens to back in the housing legislation, saying it would increase supply in the market.
"We know we need more homes in Australia to cater to the people who need a home and a roof over their head and are looking to buy their first home," he said.
"It is staggering that we are currently seeing both the Greens Party and Peter Dutton's coalition working together to block that legislation.
"(The Greens) should vote with us and get this legislation through."
