Updated at 8:19 p.m. ET

President Trump is preparing to announce changes in U.S. policy toward Cuba, possibly tightening restrictions on travel and trade that were loosened under former President Barack Obama.

Trump is expected to announce the changes in Miami on Friday.

The move was confirmed by a congressional source with direct knowledge of the situation.

Sen. Marco Rubio, R-Fla., has been leading the push for a more restrictive policy, along with his fellow Cuban-American, Rep. Mario Diaz-Balart, R-Fla.

The changes could make it more difficult for Americans to visit the island and for U.S. companies to do business there. The Obama administration ended decades of economic and diplomatic isolation of Cuba, in hopes that renewed engagement would lead to reforms in the communist country.

The White House declined to discuss the pending changes.

"When we have an announcement on the president's schedule, we'll let you know," said spokesman Sean Spicer. "But just stay tuned."

Advocates for greater engagement with Cuba warn the administration's changes could be costly.

"This is the opposite of 'America First.' This is America last," said James Williams, who leads the nonpartisan lobbying group Engage Cuba.

He warns that reduced travel and trade with Cuba could cost thousands of American jobs.

Travel to the island is already limited to visitors in 12 authorized categories, but there is little enforcement. And with renewed commercial air service, visits to Cuba have soared.

The administration is considering stepped up policing to discourage pleasure travel and limiting visitors to one trip per year.

Williams says that would be especially hard on Cuban-Americans with relatives on the island.

"Imagine, your mother is sick in Cuba," Williams said. "You might have to decide between going to see her in the hospital bed before she dies or going to the funeral. And that is just tragic."

Polls suggest a majority of Americans support greater engagement with Cuba. Last month, 55 senators sponsored legislation that would further relax travel restrictions.

The opening has also led to modest changes in Cuba, with increased revenue for small-business owners and Internet hot spots in Havana.

"I think Cubans in Cuba will be terribly disheartened" by the renewed restrictions, said Carlos Gutierrez, who served as commerce secretary under former President George W. Bush. "This decision will not play well anywhere, except for in those very cloistered spots in South Florida where Sen. Rubio and Mario Diaz-Balart have constituents."

Shortly before Trump's inauguration, Rubio said in a statement that he was heartened the new administration would reverse "the failed Cuba policy of the last two years."

When the Obama administration policy was first rolled out in late 2014, Rubio blasted the move.

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