By Anthony Harrup

MEXICO CITY -- President Enrique Peña Nieto, troubled by falling approval ratings at home, vowed Monday to protect migrants, free trade and investment as his government prepares for negotiations with the administration of President Donald Trump.

In a speech at the presidential residence outlining Mexico's position on future relations, Mr. Peña Nieto said Mexico would remain open to global trade while seeking to diversify its trade and political relations.

"We must maintain free trade between Canada, the U.S. and Mexico. Commercial exchanges among the three countries should be exempt from any tariff or quota, as has been the case since 2008," he said.

The comments came as Mr. Trump, who has said he wouldseek to renegotiate the North American Free Trade Agreement to achieve better terms for the U.S., formally withdrew the U.S. from the Trans-Pacific Partnership, a broad trade pact that includes Mexico, Canada and other Pacific nations. Mr. Trump also reiterated plans for a major border tax on U.S. companies that move production abroad.

Washington's abandonment of the TPP, which had been hopelessly stalled months before Mr. Trump's inauguration, threatens the survival of the trade agreement, which has yet to be implemented. Mr. Peña Nieto said Mexico would seek to negotiate bilateral trade agreements with members of the TPP, and was also ready to negotiate a bilateral trade deal with the U.K. once it leaves the European Union.

Mexico, which sends around 80% of its exports to the U.S. and has free-trade trade pacts with more than 40 other countries, will also bring migration and security issues to the table in its talks with the U.S.,in which it will neither seek confrontation nor be submissive, Mr. Peña Nieto said.

"While for Mexico the relationship with the U.S. is fundamental, so too for the U.S., the relationship with Mexico is of great importance," he added.

Mexico's Foreign Minister Luis Videgaray and Economy Minister Ildefonso Guajardo will lead a Mexican delegation to Washington this week to start talks with senior Trump administration officials.

Mr. Peña Nieto, who spoke with Mr. Trump by phone on Saturday, plans to visit the U.S. at the end of the month. He also spoke Sunday with Canadian Prime Minister Justin Trudeau.

Mr. Peña Nieto said Mexico would demand that the U.S. guarantee humane treatment and respect the rights of Mexican migrants, including those repatriated from the U.S., and called for the U.S. to guarantee flows of remittances Mexicans in the U.S. transfer home to their families. He also urged the U.S. to help stem the flow ofillegal weapons to Mexico.

The president criticized Mr. Trump's plans to build a wall along the U.S.-Mexico border, which Mr. Trump has said Mexico would be made to pay for. Mexican officials have repeatedly denied Mexico would do so.

"We will work for a border that unites us, not one that divides us," Mr. Peña Nieto said. "Mexico doesn't believe in walls; our country believes in bridges."

Mr. Peña Nieto's attempt to show a firm position in relation to Mr. Trump came as the Mexican leader has suffered from plunging approval ratings amid widespread protests over sharp increases in gasoline prices.

The president's speech appeared aimed at a domestic audience, said Jorge Chabat, a professor of international relations at Mexico's CIDE university. Putting security on the agenda is a good move considering its sensitivity as an issue for the U.S., Mr. Chabat said. He added Mexico's efforts to diversify trade aren't new and haven't worked well in the past. "They don't have much maneuvering room," he said.

Concerns about the impact Mr. Trump's policies could have on Mexico have helped send the peso to historic lows against the U.S. dollar, and prompted economists to lower their growth projections for this year.

The meetings between Mexico and the U.S. could help to reduce some of the uncertainty as it becomes clearer what to expect from bilateral relations, Alejandro Werner, director of the Western Hemisphere Department at the International Monetary Fund, said at a press conference early Monday.

He noted that the IMF lowered its 2017 growth outlook for Mexico to 1.7% from 2.3%, while raising its forecast for the U.S. "The only country where the effect of the uncertainty has materialized is Mexico," he said.

Write to Anthony Harrup at anthony.harrup@wsj.com

(END) Dow Jones Newswires

January 23, 2017 17:37 ET (22:37 GMT)

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