MIDGELL, P.E.I. -- U.S. Agriculture Secretary Sonny Perdue and Canada's Agriculture Minister Lawrence MacAulay emerged from a meeting in a Prince Edward Island barn Friday appearing united on trade and a modernized NAFTA agreement.

But while the two former dairy farmers agreed Canada's supply management system -- which controls the price and supply of dairy, eggs and chicken -- would remain in place, they left the barn door open for possible changes.

"We have a strong system in this country," MacAulay said during a joint news conference from his family's farm in Midgell, P.E.I., overlooking St. Peters Bay.

"We discussed a lot of things but we're not going to indicate today what changes will or will not take place in NAFTA or in the supply management system."

Perdue told reporters that the two countries benefit from open markets across the border.

"Hopefully we're moving towards a more reciprocal arrangement there that really could be, in light of NAFTA, be really free trade among North America in that way," Perdue said. "We all have our interests and Canada has an embedded supply management system in their dairy industry, and it's not our desire to do away with that, just to regulate it in a way that does not depress world prices."

MacAulay said both countries want their farmers to get a fair deal.

"We both understand that it's a win-win situation, it's not a win-lose situation," he said on his farm, where he was born, raised and worked as a dairy and potato farmer.

"What Sonny and I are doing are making sure that we have a great rapport and that we respectively defend our farmers in each country."

The bilateral meeting came at a tense time for the two countries on trade issues. U.S. President Donald Trump has said he wants the supply management system dismantled, blasting Canada for charging a 270 per cent tariff on imported dairy products.

Despite the rising tensions between Ottawa and Washington, the agriculture leaders spent what appeared to be an amicable day lobster fishing and visiting a local potato operation.

The visit offered some assurances to farmers increasingly uneasy about a mounting trade dispute between the neighbouring countries.

Alvin Keenan, co-owner of the Rollo Bay Holdings potato farm operation in Souris, P.E.I., said some of the recent tweets by the U.S. president has people "stirred up."

"It makes everybody nervous," he said, adding that there has been some "concern" about the worsening tone of trade discussions.

But Keenan said the meeting Friday between the agriculture counterparts suggested a fair deal could be struck.

"I think we'll end up with a trade agreement that we all can live with," he said. "We're neighbours ... I'm sure we will continue to do business in the future."

Agriculture is not the only source of friction between the U.S. and Canada. Trump called Justin Trudeau "weak" and "dishonest" in a Twitter tirade after the prime minister spoke against American tariffs on steel and aluminium.

On the NAFTA talks, Perdue said Friday the deal has been good for farmers across North America, but needs some renewing and modernization.

"I appreciate the president deferring his decision over withdrawing from NAFTA, which I think would have been the wrong decision," Perdue said.

When asked about a timeline for NAFTA negotiations, Perdue said: "The president, interestingly enough, is a unique negotiator -- does not respond to deadlines that much."

"We want to get it right and we want to get it done quickly," he said.

But, in keeping with the friendly tone of the news conference, Perdue told reporters he was looking forward to a "day of discovery" on P.E.I., and was eager to get his hands "down into some of that fertile-looking reddish tinge soil."

Conservative agriculture critic Luc Berthold said he hoped what appeared to be an amicable meeting is not an indication that Canada is willing to make compromises on supply management.

"(MacAulay) kept the door open to make some concessions on supply management in Canada," the Quebec MP said in a phone interview. "I think he needs to give us more detail about what for him, and for his government, is a win-win agreement."

MacAulay said he's been speaking with dairy farmers who are concerned about the situation, and the government needs to be firm in protecting the system.