The "unpredictable" nature of President Trump means the future of the North American Free Trade Agreement – now in its fourth round of negotiations – hangs in the balance, according to a source in a recent Bloomberg report.

According to the report, "U.S. negotiators in recent days put forth a string of bold proposals — on auto rules of origin, a sunset clause, government procurement and gutting dispute panels seen by the other nations as core to the pact. The moves were long-signaled, as was Canadian and Mexican opposition to them."

And Trump has warned that he might walk away from the deal altogether or perhaps give six months' notice that the U.S. is leaving NAFTA – but then not actually back out.

“He’s unpredictable, so I don’t know,” Stephen Moore, a senior economic adviser during Trump’s campaign and chief economist at the Heritage Foundation, told Bloomberg. “I do feel, though, that his bark has been worse than his bite on trade. That doesn’t mean that he’s retreating. But I think we’re going to see a NAFTA 2.0 that will find areas that will give the U.S. even greater benefits, while protecting American workers.”

Signed in 1994, NAFTA created a trilateral trade bloc in North America among the U.S., Canada and Mexico. And it has been a target of Trump's since taking office, as have other trade deals. Trump in January withdrew the U.S. from the Trans-Pacific Partnership and has threatened a similar move for NAFTA, though departing the longstanding North American deal could be trickier.

If Trump “even suggests that the United States should leave NAFTA, to undo that relationship, you would have to go back to Congress," said Richard Neal of Massachusetts, the top Democrat on the House Ways and Means committee, in a Canadian TV interview with The West Block. "And that would be a much more difficult task for him."