MEXICO CITY, May 22 (Xinhua) -- The Mexican Institute of Financial Executives (IMEF) said Tuesday that the renegotiation of the North American Free Trade Agreement (NAFTA) could last well into next year.

The postponement is because the United States and Mexico do not have enough time to conclude discussions on more complex topics ahead of potential political changes, Federico Rubli, vice president of the IMEF's national committee for economic studies.

"We believe the three countries (Mexico, the United States and Canada) have shown the goodwill to keep talking throughout 2018," Rubli told a press conference.

"With the question of Congress resolved and a new president elected in our country, the discussions can begin anew," he said.

In July, Mexico will hold general elections to select a new president and the United States will face congressional midterm elections in November.

The three countries began talks in August 2017, with the goal of concluding negotiations before the Mexican elections on July 1.

Rubli said discussions of the NAFTA had been delayed due to the complexity of certain topics, such as automotive rules of origin, the seasonal proposal for agricultural items, the dispute resolution chapter and the idea of having the treaty expire every five years.

"These topics will not be touched until the end of this year, at least," Rubli said.

On May 19, Mexico's chief technical negotiator, Kenneth Smith, said that about nine out of some 30 chapters in the original agreements have been nailed down.

Rubli said another factor of uncertainty is the "volatile" temper of U.S. President Donald Trump, who has repeatedly threatened to scrap NAFTA altogether.

"There is nothing that can stop him tomorrow, or in a month, or at any time, from getting up in the mood to quitting the treaty. That is something we must always reckon with," he said.

"Obviously, the important thing is to not go back on what has already been agreed and what has been worked on this year," he added. Enditem