American trade officials are set to resume talks with their Canadian counterparts to try to salvage the North American Free Trade Agreement as a trilateral accord.

After months of intense negotiations, the US and Mexico announced an agreement Monday to revise of the 25-year-old free trade pact but US President Donald Trump suggested he could cut Canada out of the deal.

Canadian Prime Minister Justin Trudeau stressed to Trump in a phone conversation on Monday that his aim was to negotiate a new NAFTA deal.

Trump and Trudeau “had a constructive conversation” on NAFTA, and “look forward to having their teams engage this week with a view to a successful conclusion of negotiations,” Trudeau’s office said.

Canadian Foreign Minister Chrystia Freeland cut short a trip to Europe to travel to Washington to begin negotiations with US Trade Representative Robert Lighthizer. However, it is not clear when exactly they will begin their talks.