After nearly three years of warming relations between the United States and Cuba, President Donald Trump has announced that his administration will unravel many of his predecessor’s policies on the communist state.

Speaking from Miami, Florida, Trump announced changes to President Obama’s historic rapprochement with Cuba — fulfilling a promise to the anti-Castro voting bloc he believes helped his campaign clinch the state, but stirring fear among others he could set back business interests and Cuba’s potential for a more prosperous private sector.

In one form or another, the embargo on Cuba has been in place since the Eisenhower administration. But beginning in late 2014, President Barack Obama and Cuban President Raul Castro began a process that gradually thawed diplomatic tensions and eased commercial and travel restrictions between the two countries.

Hundreds of millions of U.S. dollars flowed into privately owned businesses in Cuba, The Associated Press reported