OTTAWA -- Negotiations on a major international trade deal involving Canada appear to have hit last-minute snags in what were supposed to be the final stages of talks.

Canadian officials are in Hawaii where a dozen countries, including the United States and Japan, have been trying to reach an agreement called the Trans-Pacific Partnership.

A spokesman for Canada's international trade minister says Prime Minister Stephen Harper will only sign an agreement that's in Canada's best interests.

Earlier this week, a trade envoy from New Zealand said Canada's refusal at the bargaining table to offer more foreign access to its dairy market could slow up negotiations.

On Friday, the U.S. Trade Department delayed a scheduled news conference on the progress of negotiations from 7:30 p.m. ET until 10 p.m. ET.

Ottawa says the countries in the partnership represent some 800 million people with a combined gross domestic product of roughly 40 per cent of the global economy.

Harper has also said Canada "cannot be left out of this kind of trade arrangement."

Supporters of the deal say it would create openings for Canada in dynamic Asian markets for the first time and, in particular, Japan -- the world's third-largest economy.

Trade experts argue Canada can't afford to miss out on a massive deal they say would help many domestic industries, including the services sector as well as beef and pork producers.

But a decision by the Harper government to loosen supply management of the dairy sector would be politically sensitive, particularly with the ruling Conservatives expected to kick off an election campaign as early as Sunday.

The prospect of opening up access to the market has been met by strong opposition from dairy farmers and has even led to protests.