Mexican Secretary of Economy Ildefonso Guajardo Villarreal, pictured October 2017, says that the steps to reach agreement could allow Canada to rejoin talks

Washington (AFP) - US and Mexican negotiators have made progress in narrowing differences on the update of the North American Free Trade Agreement, Mexico’s Economy Minister Ildefonso Guajardo said Thursday.

The steps to reach agreement could allow Canada to rejoin talks next week, he told reporters as he entered meetings for the second day with US Trade Representative Robert Lighthizer.

US and Mexican officials have said they aim to conclude discussions this month and it is the third straight week ministers have traveled to Washington for meetings.

Teams worked through the night “changing the text” and “got a lot of work done,” Guajardo said.

But the thornier issues are being left to the end, including the US demand that NAFTA be approved every five years, a provision known as a sunset clause.

“We are organizing the items according to the degree of complexity and sunset clause is the very last,” he said.

Mexico has repeatedly said it opposed to including such a clause.

The US and Mexican teams have spent a lot of time on issues involving the auto industry and Guajardo said earlier this week they had reached an agreement on the US demands that a share of vehicle components with duty-free treatment come from countries with high wages.

A USTR spokeswoman declined to comment on the content of the discussions.

Asked if Canada would rejoin the NAFTA talks next week, Guajardo said, “Hopefully. We have to make sure that the US-Mexico bilaterals are done.”

But there is no specific date to return to trilateral discussions, he said.

Foreign Minister Luis Videgaray, who accompanied Guajardo, spoke to US Secretary of State Mike Pompeo on Wednesday and “discussed the importance of concluding a NAFTA agreement,” according to a statement from the State Department.

Talks are due to continue Friday and include Jesus Seade, economics adviser to Mexico’s President-Elect Andres Manuel Lopez Obrador.

US President Donald Trump demanded NAFTA be renegotiated after repeatedly criticizing the 24-year-old pact as a “terrible deal” and officials now are rushing to conclude the talks before Lopez Obrador takes office on December 1.