WASHINGTON -- U.S. president Donald Trump has notified Congress that his administration intends to sign a trade agreement in 90 days with Mexico and Canada - if Ottawa decides to join in.

The message was sent after NAFTA talks with Ottawa failed to produce a deal before Trump's Friday deadline.

Canadian and American negotiators will return to the bargaining table next Wednesday after a week of talks produced few signs the sides would budge on their most stubborn NAFTA positions.

“Today the president notified the Congress of his intent to sign a trade agreement with Mexico - and Canada, if it is willing - 90 days from now,” U.S. Trade Representative Robert Lighthizer said in a statement Friday.

“We have also been negotiating with Canada throughout this year-long process. This week those meetings continued at all levels. The talks were constructive, and we made progress. Our officials are continuing to work toward agreement.”

Foreign Affairs Minister Chrystia Freeland is set to make an announcement on the state of the NAFTA talks later Friday at the Canadian embassy in Washington.

Freeland is expected to announce that her intense, days-long talks with her American counterpart have progressed, but that they will take a break for the long weekend and resume next week.

Throughout the day Friday, it became increasingly clear that Canada and the U.S. would be unable to reach an agreement. Dispute settlement, Canada's cultural exemption and access to Canada's dairy market remain obstacles to a deal.

Lighthizer's office accused Canada of making no compromises on dairy-market access.

Similarly, Canadian officials told The Canadian Press early on Friday that expectations a NAFTA deal is imminent were exaggerated and premature.

Friday's talks were coloured by Trump's blunt assessment of the negotiations - spoken in confidence but leaked to the media - that landed with a thud on the negotiating table.

Trump, in a conversation Thursday with Bloomberg News, gave a dismissive off-the-record assessment of the Canadian position on major NAFTA sticking points that was leaked to the Toronto Star newspaper.

“If I say no - the answer's no. If I say no, then you're going to put that, and it's going to be so insulting they're not going to be able to make a deal ... I can't kill these people,” Trump said of the Canadian government, according to the Star report, which cited an anonymous source.

Any deal with Canada would be “totally on our terms,” Trump was quoted by the Star as saying.

Trump confirmed the authenticity of the remarks in an afternoon tweet.

“Wow, I made OFF THE RECORD COMMENTS to Bloomberg concerning Canada, and this powerful understanding was BLATANTLY VIOLATED,” Trump wrote.

“Oh well, just more dishonest reporting. I am used to it. At least Canada knows where I stand!”

As word of Trump's off-the-record remarks rippled through the media corps gathered outside the offices of the U.S. trade representative on Friday morning, a stoic Freeland maintained her diplomatic countenance, saying only that both the Canadian negotiating team and USTR officials were working hard to reach an agreement.

“We're not there yet,” she cautioned.

Asked directly about Trump's remarks and whether the Americans are bargaining in good faith, Freeland walked a diplomatic tightrope.

“Ambassador Lighthizer and his team, throughout this negotiation, have been working really, really hard,” Freeland said.

“Our starting positions at the beginning were very far apart. I think, at this point, we know what each side needs and we're working hard to find a way. My job is to find the deal that works for Canada...

Trump, according to the Star report, also said he frequently reminds Canada that if necessary he will slap painful tariffs on auto imports. Such a move, experts warn, would inflict heavy damage on the countries' deeply integrated auto sector.

“Off the record, Canada's working their ass off. And every time we have a problem with a point, I just put up a picture of a Chevrolet Impala,” Trump said, according to the article.

The Impala is manufactured at the General Motors plant in Oshawa, Ont.

Prime Minister Justin Trudeau held an event Friday in Oshawa, where he announced a government investment towards the creation of new automotive jobs.

Trudeau was asked by journalists about the reports on Trump's off-the-record comments. He replied that “over the past year and a half there's a lot of things that have been said from time to time.”

He wouldn't comment on the obstacles that remain and reiterated he won't negotiate in public.

“We're going to remain constructive, positive, serious and creative about what we do around the negotiating table… We are also going to be unequivocal about always standing up for Canadians' rights and Canadians' interests.”

This week's new round of U.S.-Canada negotiations had initially generated hopeful signals from both camps that a deal could be struck by the end of the week - but difficult discussions about dairy and dispute settlement persisted.

Trump has repeatedly criticized Canada's dairy industry and has used the threat of tariffs on Canada's auto production to push for concessions. But Canada's dairy industry is adamant that it won't stand for the government allowing the U.S. any more market access, saying it has compromised enough on past trade deals with the European Union and Pacific Rim countries.

Another lingering sticking point is Chapter 19, set up to resolve disputes among the three countries and industry around how to implement NAFTA rules. The U.S. wants it out of the deal, but Canada says it must be included.

-- With files from Mike Blanchfield and Andy Blatchford in Ottawa