US President Donald Trump said on Wednesday the United States may hammer out a trade deal with Mexico, and then do a separate one with Canada later, sowing fresh doubts about the future of the North American Free Trade Agreement (NAFTA), Reuters reported.

“We have had very good sessions with Mexico and with the new president of Mexico, who won overwhelmingly, and we’re doing very well on our trade agreement,” Trump said to reporters ahead of a meeting of his cabinet at the White House.

“So we’ll see what happens. We may do a deal separately with Mexico and we’ll negotiate with Canada at a later time. But we’re having very good discussions with Mexico.”

Trump pledged during his election campaign to revamp the 24-year-old NAFTA trade deal between the United States, Canada and Mexico, which he has called a disaster for the United States.

However, the negotiations that started last August have moved slowly. They were initially scheduled to finish by the end of 2017, but the deadline has been extended several times as Canada and Mexico struggle to accommodate U.S. demands.