Labor claims a new Pacific region trade pact is in line with its values and rejects suggestions from the Turnbull government that it will veto the agreement.
Eleven nations including Australia are set to sign a revised Trans-Pacific Partnership on March 8 in Chile, despite the United States withdrawing.
The federal opposition says independent modelling is needed before parliament approves the deal.
But Treasurer Scott Morrison says Labor is stalling and modelling is not needed to prove "economic common sense".
"Labor would think you'd need economic modelling to decide whether you put your pants on one leg at a time," Mr Morrison told Sky News on Thursday.
However, Labor frontbencher Richard Marles said there was a "lot of politics" in Mr Morrison's comment.
"If you look at Labor's history and how we go about things right now, we have always been in favour of trade liberalisation," he said.
"The TPP itself really is the practical trade manifestation of APEC and the Hawke-Keating (Labor) government was absolutely instrumental in having APEC established."
Labor leader Bill Shorten said his party was open to considering the agreement, as it had done with other recent free trade deals.
"If you're buying a car, you don't get the mechanic's report after you've bought it," Mr Shorten told reporters in Brisbane.
"Let's see the evidence, and we'll back it 100 per cent. If it's a dud deal, then the worst that's happened is we've stopped a dud deal from going through."
Greens leader Richard Di Natale said Labor needed to make its position clear immediately.
On Wednesday the prime minister - who is expected to hold talks with US President Donald Trump in February - said while he would encourage the US to come back into the TPP, he didn't think there was "any prospect" of it.
However the trade deal includes provisions for the US to join.
