Al Zapanta, head of the U.S.-Mexico Chamber of Commerce, stands next to David Abshire, right, founder of the Center for Study of the Presidency and Congress, during a luncheon. (The Washington Post)

The business leader expected to top the shortlist for President-elect Donald Trump’s ambassador to Mexico has launched a broad effort to promote stronger U.S.-Mexico ties and reassure leaders after Trump vowed unilateral action that would upend relations between the two countries.

Al Zapanta, the head of the U.S.-Mexico Chamber of Commerce and chief executive of natural-gas development company Paz Resources, is launching what he calls the North American Working Group at a meeting of business leaders Friday in The Woodlands, Tex. The group is an assembly of corporate executives and former policymakers in the United States and Mexico who will study and craft policy proposals in eight broad areas, such as ­immigration and trade. They plan to present their conclusions to Trump in the spring.

Zapanta said that he is in touch with Trump’s son Donald Trump Jr. and senior Trump adviser Stephen K. Bannon as the effort moves forward “in parallel to” the official transition. But Zapanta said the president-elect was not sending a representative to the first summit.

“I’m it,” Zapanta, who supported Trump’s campaign, said in an interview. “I’m actually trying to keep it as pure as I can. We really pride ourselves on being a third-party, honest broker.”

Spokesmen for Trump’s transition team did not respond to a request for comment.

The working group is the largest outside effort of its kind to date, with eight task forces ­devoted to energy, trade, infrastructure, manufacturing, agriculture, ­immigration, technology and health. Each group will mix ­private-sector executives and former policymakers from both sides of the political debate, Zapanta said. He said that he will travel to ­Mexico City in two weeks to meet with other participants drawn from Mexico’s business elite.

Zapanta, who also runs Planning Inc., which offers training services to federal agencies and private firms, said that he has not been offered the position of U.S. ambassador to Mexico and that he is not directly in touch with Trump on a regular basis.

“The answer is: Am I a potential candidate? Of course,” he said. “What else can I say? I have not sat down and had my interview with anybody.”

Zapanta’s project is set to enter rocky territory as Americans recover from a campaign defined in part by Trump’s bruising rhetoric toward Mexico and promises to deport millions of undocumented immigrants, build a border wall with Mexican funds and renegotiate the North American Free Trade Agreement. While the president-elect appears to have softened some of his positions since his Nov. 8 victory, many of his plans remain unclear.

Some Republicans consider Zapanta, a Purple Heart recipient known to friends as “the General,” to be among the few ­non-ideologues Trump takes seriously on these matters. According to people who were in the room, Zapanta seemed to make an impression on Trump over the summer at a meeting when he spoke frankly about Hispanic American heritage and the practical considerations of building a border wall.

In the recent interview, ­Zapanta played down his disagreements with Trump on issues such as the wall, which he said should be less a vast, uniform physical barrier than a “smart border” that uses ­technology to ­enhance ­security. “You could call it a ‘smart wall,’ whatever,” Zapanta said. “You’re really looking at a digital application that connects all the ­elements: people, ­commerce, cyber, banking, you name it.”

He also denied that Trump would “throw out” NAFTA, a deal Zapanta has promoted since its inception. Trump “said he wants to look at how NAFTA can be adjusted or added to or whatever the future would hold,” Zapanta said.

“A lot of the uneasiness [among Mexican leaders] is because of the unknowns,” he said. “Well, those are to be determined and to be discussed and to be negotiated. At the end of the day, our neighbors aren’t going anywhere, and neither are we, and we need to find ways to make it work.”