Powerful U.S. corporations led by its leading commercial airlines will make it difficult — maybe impossible — for President-elect Donald Trump to nix President Barack Obama’s Cuba outreach, the White House warned Monday.

Commercial carriers soon will operate 110 daily flights between the United States and Cuba and have a lot to lose financially if Trump carries through on a threat issued Monday via his Twitter account. “If Cuba is unwilling to make a better deal for the Cuban people, the Cuban/American people and the U.S. as a whole, I will terminate deal,” Trump wrote.

White House Press Secretary Josh Earnest said power players in transportation and other sectors cleared by the White House to begin doing business in Cuba will throw up hurdles if Trump follows through.

[Obama to Cuba, Will Huddle With Raul Castro]

“Unrolling all of that is much more complicated than just the stroke of a pen,” Earnest said of the list of administration policies and U.S. corporate investments already in place or in the works.

Earnest described the likelihood of Trump nixing the Obama administration’s deal with the Cuban government as “rather remote,” also citing popular support at home for closer ties between the countries.

The White House has set the two countries on a path to formally normalized relations. But during the presidential campaign, Trump was critical of thawing relations with the island nation. Cuba hit another milestone Monday when American Airlines operated its first scheduled flight from Miami to Havana.

The back-and-forth came just three days after longtime Cuban leader Fidel Castro passed away at age 90. Many Republicans panned Obama for issuing a written statement that, in their view, focused too little on Castro’s violent and oppressive tenure. The White House on Monday answered its critics.

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There should be no “whitewashing” of many violent and oppressive actions the former Cuban leader ordered that “go against” U.S. values, Earnest said. But, as the Obama administration tries to secure top legacy items ahead of Trump taking office, he added that U.S. officials “can’t let the past interfere with our ability to make progress.”

Incoming White House Chief of Staff Reince Priebus told “Fox News Sunday” his boss would “absolutely” nix the deal unless there is “some movement” in issues like “repression, open markets, freedom of religion, political prisoners” from the Cuban government, now led by Fidel Castro’s brother, Raul Castro.

But Kellyanne Conway, Trump’s campaign manager and now a close adviser, told ABC News on Sunday that the president-elect has yet to decide just what to do about Cuba.

Contact Bennett at johnbennett@cqrollcall.com. Follow him on Twitter @BennettJohnT.