New Zealand's special agricultural trade envoy at the TPP talks in Hawaii has cast doubt on whether the trade deal is going to be acceptable to New Zealand.
Negotiators from the 12 countries in the talks are meeting in Hawaii in an effort to wrap up the deal this week.
Mike Petersen said more concessions on dairy products were needed before New Zealand could sign the Trans Pacific Partnership agreement.
He told Morning Report progress at the talks were slow, and on dairy alone at this stage, the deal was not good enough.
"The deal's simply not at the stage where the industry could support it or even New Zealand could really accept this deal.
"This is pretty precarious here at the moment.
"Everyone knows that dairy's a major sticking point and we're needing much greater progress in that area if we're going to put this deal to bed by the end of the week."
Nations with large and protected industries were "pushing back".
"Countries like the USA and Canada and Japan really need to make more progress on dairy so that we can get a good outcome for dairy across the board."
Mr Petersen said other nations in the talks were saying this was simply a New Zealand problem, but his view was that a weak outcome for dairy would be a problem for all countries.
"I am confident we'll get there in the end, but I have to say that until now things have been very slow," he said.
But ministers were now "on task" and a series of bilateral meetings were held yesterday.
"We're expecting some significant movement to make this deal one that is attractive to New Zealand."
Clayton Yeutter, an international trade adviser in Washington, said he had high respect for Mr Petersen and what he says should be taken seriously.
But he said a lot could happen in the last 48 hours of talks like these, and he was more optimistic about the outlook than Mr Petersen.
The veteran trade adviser gave the talks only a 50-50 chance of reaching a conclusion this week that satisfied all 12 negotiating countries.
He said Japan's reluctance to open up its dairy market was a major sticking point.
Beef + Lamb New Zealand says the deal could save New Zealand millions of dollars in tariffs on meat.
Its trade policy and advocacy senior manager, Tracey Paterson, says that along with marketing organisations from the US, Canada, Mexico and Australia, Beef + Lamb had been lobbying hard for lower tariffs in the lucrative Japanese market.
She told Morning Report cutting the current import tax on beef in Japan from 38.5 percent to about 9 percent would save New Zealand $50 million a year.
New Zealand is negotiating the TPP with the United States, Australia, Brunei Darussalam, Canada, Chile, Japan, Malaysia, Mexico, Peru, Singapore, and Vietnam.