MEXICO CITY — The Mexican Senate approved a new North American trade agreement on Wednesday, making Mexico the first country to ratify a deal that President Trump has touted as his signature trade achievement.

“Mexico takes the lead, with clear signals that our economy is open,” Jesús Seade, Mexico’s top trade negotiator, wrote on Twitter, celebrating the Senate’s approval of the bill. “We trust that our partners will soon do the same thing in the interest of a strong North America, with clear rules, that is stable, competitive and attractive for investment.”

The accord, known as the United States Mexico Canada Agreement, was signed late last year by the leaders of the three countries. For it to go into effect, it has to be approved by the legislatures of all three countries.

The path to approval has been bumpiest in Washington, where Democrats in Congress have raised concerns over Mexico’s enforcement of labor rights and environmental law — and smoothest in Mexico, where the president has described the accord as a guarantee of stability for his country’s economy.