The U.S. may decide over the weekend to delay hiking tariffs on goods from Mexico as talks progress over steps Mexico can take to stem the surge of illegal immigration from Central America, a top White House official said Friday.

Marc Short, Vice President Mike Pence’s chief of staff, said the U.S. plans to file an official notice today that would raise tariffs effective Monday but that these could be delayed or canceled over the weekend by President Donald Trump.

“There’s a legal notification that goes forward today with a plan to implement tariffs on Monday, but I think there is the ability, if negotiations continue to go well, for the President to turn that off at some point over the weekend,” Short said Friday morning.

Short said, however, that “there’s a long way to go still” before an agreement can be reached.

A delegation from Mexico has been meeting with members of the Trump administration since Wednesday and talks are continuing today. President Trump is returning from a trip to Europe and will be briefed on the talks when he returns, according to White House officials.

White House economist Kevin Hassett said that the talks “have proceeded very favorably.” He also appeared to indicate that the president might be inclined to hold off on hiking tariffs.

“There’s been a lot of talks, a lot of progress made,” Hasset said in an interview on CNBC’s “Squawk on the Street” Friday morning. “I think that people feel like they’re going to be presenting to the president when he gets back some positive choices.”