MEXICO CITY, Sept. 18 -- Mexican Economy Minister Ildefonso Guajardo said here on Monday his government was confident that important advances can be made during the third round of renegotiations for NAFTA.

Participating at a Forbes business forum, Guajardo said only four NAFTA (North American Free Trade Agreement) chapters would be discussed in the third round of seven planned renegotiations in Canadian capital Ottawa from Sept. 23-27.

The first two rounds, held in Washington and Mexico City, saw the three teams present their concepts and proposals for the renegotiation.

"We decided to begin with those topics that have proposals and could structurally be closed more rapidly," he said.

The minister, who is also the chief negotiator for Mexico, told journalists that these four topics include small and medium enterprises and their integration in value chains, transparency, agriculture and sanitary regulations.

Guajardo also recognized that 12-13 chapters present "important degrees of difficulty," such as the U.S. proposal to eliminate Chapter 19, which covers dispute resolution, as well as the matter of rules of origin in the automotive sector.

NAFTA, in vigor since 1994, is renegotiated at the demand of U.S. President Donald Trump, who said during his campaign that NAFTA was the worst free-trade deal signed in American history and that it had hurt the country's manufacturing and employment.