New Zealand is about to increase the pressure on the United States to open up access for this country's exports to its highly protected dairy markets.
The latest round of negotiations for the 11-country TransPacific Partnership trade deal started in Auckland on Monday.
Five hundred negotiators are meeting behind closed doors at Sky City for nine days to thrash out a deal.
The pressure has gone on the countries after US President Barack Obama last month named October next year as the deadline for a completed deal.
Trade Minister Tim Groser says now is the time for the US to lay its cards on the table on market access for New Zealand dairy exports.
"We have been following very, very deliberately a strategy of not trying to push beyond what the political traffic would bear but now is the moment to start to change that."
New Zealand's special agricultural envoy Alistair Polson says nothing short of total elimination of tariffs on exports to America will do.
But Lori Wallach from the trade watchdog Public Citizen says even if American negotiators cave in, any deal could still be derailed by members of Congress beholden to powerful domestic dairy interests.