With a 12:01 a.m. ET deadline looming on Saturday, the United States and Canada are racing to strike a deal that could determine whether steep tariffs on billions of dollars worth of Canadian goods take effect — a move that would mark a major escalation in the trade war.

Earlier this week, President Donald Trump granted a three-day delay for 50% tariffs on $20 billion of Canadian exports to the US, telling reporters that a deal had been reached to avert the levies, pending final negotiation.

“We’ve come to a deal with Canada,” Trump said on Wednesday. “We’re going to give something, and we’re doing certain things,” he added, without elaborating further.

Canada-US Trade Minister Dominic LeBlanc was spotted Friday outside the US Trade Representative’s office in Washington, where he was expected to meet with Trump’s top trade official, Jamieson Greer. The two met multiple times throughout the week as well. After Thursday’s meeting, LeBlanc said the two sides were “very close” to reaching a deal.

But no deal has emerged yet, underscoring the remaining sticking points in the talks.