Carlos Barria / Reuters Prime Minister Justin Trudeau is greeted by U.S. President Donald Trump at the White House in Washington on Feb. 13, 2017.

OTTAWA — Justin Trudeau will visit the North American capitals next week amid early signs of turbulence in continental trade negotiations that have stoked some concern from NAFTA supporters about the agreement's long-term prospects.

The prime minister will meet U.S. President Donald Trump during a two-day visit to Washington, followed by a meeting with Mexican President Enrique Pena Nieto during a two-day visit to Mexico City.

The trip was not specifically designed around NAFTA, say Canadian officials, noting that it was in the works for some time and began with an invitation to a women-in-business summit in Washington, coupled with Trudeau's long-standing plan to visit Mexico.

But trade will come up, they said.

'Ridiculous' American provision

Some officials have been unnerved by early sticking points that have emerged even before the negotiations touch the hardest issues: dairy, auto parts, the dispute-resolution system and the U.S. idea of forcing a mandatory review of NAFTA every five years.

A rare major file that has already opened involves so-called Buy American rules. And America's neighbours were dismayed by the U.S. proposal during the last round in Ottawa: that access to U.S. public works be restricted to a one-for-one ratio — a dollar's worth of U.S. contracts for every dollar of contacts across the border.

Whether they're just driving a hard bargain (or serious about this idea, we) don't know.NAFTA official

"Which is ridiculous,'' said an official in one of the other NAFTA countries.

"Whether they're just driving a hard bargain (or serious about this idea, we) don't know.''

Canada's position is that it's unrealistic to expect perfect reciprocity given massive differences in market size. It has pushed back against some of the numbers cited by fans of Buy American rules, who argue the U.S. offers nearly 100 times more access to government procurement ($198 billion) than it gets from Canada ($2.25 billion at the federal level).

The Canadian embassy recently sent Washington lawmakers a letter citing a counter-statistic: that just three per cent of U.S. federal contracts are won by foreign suppliers, while 11 per cent of Canadian federal contracts go to foreign firms.

Earlier on HuffPost:

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