The Trump administration bans group educational and cultural trips known as ‘people to people’ travel to the island.

The Trump administration on Tuesday imposed major new travel restrictions on visits to Cuba byUnited States citizens, including a ban on many forms of educational and recreational travel.

The Treasury Department said in a statement that the US will no longer allow the group educational and cultural trips known as “people-to-people” travel to the island. Those trips have been used by thousands of American citizens to visit the island.

Treasury said it would also deny permission for private and corporate aircraft and boats. However, commercial airline flights appear to be unaffected and travel for university groups, academic research, journalism and professional meetings will continue to be allowed.

The end to group educational travel would likely deal a heavy blow to American tourism on the island, which took off after former President Barack Obama moved to ease the half-century embargo against the Cuban government in 2014.

“It kills the people-to-people category, which is the most common way for the average American to travel to Cuba,” said Collin Laverty, head of Cuba Educational Travel, one of the largest Cuba travel companies in the US.

Treasury Secretary Steven Mnuchin said the measures were a response to what it called Cuba’s “destabilising role” in the Western Hemisphere, including support for the government of President Nicolas Maduro in Venezuela. Most Western countries recognise Venezuelan opposition leader Juan Guaido as the country’s legitimate president, while countries including Cuba, Russia, China and Turkey continue to support Maduro.

“Cuba continues to play a destabilising role in the Western Hemisphere, providing a communist foothold in the region and propping up US adversaries in places like Venezuela and Nicaragua by fomenting instability, undermining the rule of law, and suppressing democratic processes,” Mnuchin said. “This administration has made a strategic decision to reverse the loosening of sanctions and other restrictions on the Cuban regime. These actions will help to keep US dollars out of the hands of Cuban military, intelligence and security services.”

The new restrictions had been previewed by national security adviser John Bolton in an April speech in Miami to veterans of the failed 1961 Bay of Pigs invasion but details of the changes were not made public until Tuesday. Treasury said the sanctions would take effect on Wednesday after they are published in the Federal Register.

Cuban officials did not immediately comment on Tuesday’s announcement.

After President Donald Trump came to office in January 2017 promising to reverse Obama’s thaw with Cuba, he banned individual visits and, in a series of moves, limited commercial interactions with the country.