A group of Federal Labor MPs say they have been conned into supporting a Greens bill they believe could pave the way for same-sex marriage.

At Labor's caucus meeting on Tuesday, MPs took just minutes to support the Greens bill.

It would give the Federal Parliament, rather than the Federal Government, power to override territory laws.

But when it emerged the bill could pave the way for same sex-marriage in the territories, a group of Labor MPs was enraged.

They say the implications of the bill were not properly explained.

Several have told the ABC they suspect it was a deliberate stitch up by the Labor left and Greens MPs who support gay marriage.

A delegation fronted Prime Minister Julia Gillard with their concerns after a series of meetings yesterday.

The bill was to be voted on today, but has now been delayed while a Senate inquiry is held.

One MP says the party is not properly scrutinising Greens bills and is in danger of allowing the Greens to hijack the agenda.

The MP says the task of dealing with the Greens is becoming a drag and will only get worse from July when they hold the balance of power in the Senate.

But left-wing Labor Senator Doug Cameron says members of the right have overreacted to the bill.

He says it does not relate to gay marriage and is simply about the territory rights.

"The issue of same-sex marriage will obviously be debated at the National Conference of the ALP and people should just calm down and wait until that debate comes on," he said.

"Let's have the debate on the facts, not on some paranoia that's around."

Nationals MP Darren Chester says Labor members are right to be concerned as the bill is evidence the Greens are driving Labor's agenda.

"Labor members are very concerned, they've just started to realise they've got prime minister Bob Gillard, or is it prime minister Julia Brown, they're not too sure at the moment," he said.

"There's a people's revolt going on within the Labor Party and they're very concerned about the direction the Greens are taking their party."

But Greens leader Bob Brown says the people arguing against the bill do not have much seniority, and he is confident it still has the support of the party.

"Goodness knows who's influenced them to get worried about this, but if any of them want to come and talk to me I'll explain why it's an extremely good bill, why it should proceed and why it will enhance democracy," he said.

"The Government's support hasn't been withdrawn so far as I know."

And Greens Senator Christine Milne says the outburst is just a sign of "growing pains" in the Parliament.

"I think it's taking a while for people to realise there isn't a majority government in Australia, they don't have control of either house on their own," she said.

"And it requires everybody on all sides of politics; the Coalition as well as the Govt as well as the crossbenchers to get together and work things out."

She says the aim of the bill is to give Australian's living in the territories the same rights as the rest of the country.

"This is a basic principle in our democracy, why shouldn't people who live in the ACT or the Northern Territory have the same rights in terms of their parliament, then democracy as in any other state," she said.