OTTAWA -- A third round of NAFTA renegotiations has begun with chief negotiators from Canada, the U.S. and Mexico meeting in the Canadian capital.

Canada's chief negotiator, Steve Verhuel, said Saturday that he doesn't expect this round to see any new U.S. proposal to increase American content requirements for autos. U.S. Trade Representative Robert Lighthizer has said he wants to see an increase.

NAFTA now says vehicles must have at least 62.5 per cent North American content to qualify for duty-free movement between Canada, the U.S. and Mexico.

US Trade Representative spokeswoman Emily Davis declined to say what is on the agenda for Saturday.

Negotiators are trying to meet a deadline set for the end of the calendar year.