Cubans said they were crestfallen to be returning to an era of frostier relations with the US as the news spread that US President Donald Trump was set to revert parts of the historic detente with Cuba.

Trump yesterday was set to announce a plan to tighten rules on Americans travelling to Communist-run Cuba and significantly restrict US firms from doing business with Cuban enterprises controlled by the military, White House officials said.

"It hurts to be going backwards. To roll back the engagement will only manage to isolate us from the world," said Havana resident Marta Deus.

A landmark agreement to normalise relations between the former Cold War foes was made between former US President Barack Obama and Cuban leader Raul Castro in 2014. An increased arrival of US tourists, thanks to eased restrictions, had fuelled a boom in tourism, especially in Havana. But critics say the opening failed to improve rights on the island. Trump will justify his partial reversal of Obama's measures to a large extent on those grounds, White House officials said, and some Cuban dissidents back his tougher stance, saying repression has worsened since the detente.