President Joe Biden’s top trade negotiator plans to travel to Mexico City next week for meetings with her counterparts from Mexico and Canada as the governments seek to build on their free-trade deal that took effect a year ago.

Katherine Tai is due to head to the Mexican capital for meetings on Wednesday with Mexican Economy Minister Tatiana Clouthier and Canadian Trade Minister Mary Ng, according to people familiar with the plans, who asked not to be identified before a public announcement. It will be her first trip to Latin America and second trip abroad following travel to Europe in June.

The press offices of the U.S. Trade Representative, Mexican Economy Ministry and Canadian Trade Ministry declined to comment.

At the inaugural meeting of the pact’s Free Trade Commission last month, Tai expressed strong concern about Mexico’s policies that appear to disadvantage U.S. investments, especially in the clean and renewable energy sector, according to an American official. The three nations also discussed workers’ rights.

Attention on labor issues increased after the U.S. in May asked Mexico, under the deal’s rapid-response mechanism, to review whether employees at a General Motors Co. facility are being denied their rights. The AFL-CIO—the U.S.’s biggest labor-union federation—filed another complaint. Mexico responded by raising concerns about conditions for workers in the U.S. agriculture and meat-packing sectors.

The Mexican government has since told the U.S. that it’s ready to work with the Biden administration to draw up a plan to remedy the denial of workers’ rights at the GM pickup-truck plant in Silao, Guanajuato.

Tai is playing a key role in setting and implementing Biden’s trade policy, which they both have promised to focus on workers and the middle class. She told lawmakers at a hearing in May that she plans to use the available tools via the U.S.-Mexico-Canada Agreement to ensure that the other countries honor their commitments made under the deal.

The American energy industry says Mexico is discriminating against U.S. companies after pushing through major changes to electricity and hydrocarbons laws. They amend market rules to favor state-owned Petroleos Mexicanos and electric utility Comision Federal de Electricidad over private firms.

Tai was the chief lawyer for House Democrats seeking to strengthen the USMCA’s labor provisions after the deal was initially reached between Trump with Mexico and Canada in 2018. The changes she helped negotiate between House Speaker Nancy Pelosi and the Trump administration on the revamped North American Free Trade Agreement were pivotal in winning overwhelming bipartisan majorities in the House and Senate in late 2019 and early 2020.

Today marks the one-year anniversary of the deal entering into force.