Mexico’s President Andres Manuel Lopez Obrador sought to resolve a contentious issue with the United States over Mexico’s energy policy by asserting that Washington had changed its stance and was now more respectful of his position.

On the same day that he spoke, top American diplomats led by Secretary of State Antony Blinken were scheduled to meet with their Mexican counterparts in Mexico City to discuss economic cooperation.

In July, the U.S. trade representative demanded dispute settlement talks with Mexico, arguing Lopez Obrador’s drive to tighten state control of the energy market was unfair to U.S. companies and likely in breach of a regional trade deal.

Lopez Obrador, who has cast his energy policy as a matter of national sovereignty, at the time responded defiantly, saying he would defend Mexico’s position at an independence day military parade taking place this coming Friday.

However, on Monday he said he would no longer refer to the energy dispute during his Friday speech because U.S. President Joe Biden had responded to his concerns positively.

“There’s a different tone. There’s a respectful attitude. Rather, it’s a reaffirmation of respect for our national sovereignty,” Lopez Obrador told a regular news conference, referring to a letter he said had received from Biden.

The U.S. energy complaint, which Canada immediately joined, is arguably the biggest dispute to surface under the United States-Mexico-Canada Agreement (USMCA) since the North American trade deal came into effect in 2020.

If unresolved, it could lead to the imposition of hefty trade tariffs against Mexico, analysts say.

Mexican Foreign Minister Marcelo Ebrard said last week the energy dispute was not on the agenda for Monday’s U.S.-Mexico High Level Economic Dialogue.

However, talks over the dispute have been underway for weeks, and it could feature on the sidelines.

Blinken and U.S. Commerce Secretary Gina Raimondo were welcomed at Mexico City airport by Ebrard in late morning for talks due to focus on semiconductors, telecommunications, medical equipment among other economic issues, Mexico said.

Blinken is also due to meet Lopez Obrador during his visit.