President-elect Donald Trump on Monday threatened to scrap efforts taken by President Barack Obama aimed at slowly normalizing relations between the US and Cuba.

“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 on Twitter.

Trump’s warning came just days after the death of Fidel Castro, the communist island dictator who held power for decades.

Warming relations with the communist island had been one of Obama’s top priorities in his second term.

In late 2014, Obama moved to end the decades-long freeze in relations with Cuba. In 2015, the two countries announced they would reopen embassies and restore diplomatic relations.

Reince Priebus, the incoming chief of staff to Trump, told Fox News on Sunday that Trump would demand certain “changes” be made by the Cuban government.

“Repression, open markets, freedom of religion, political prisoners — these things need to change in order to have open and free relationships, and that’s what President-elect Trump believes, and that’s where he’s going to head,” Priebus said.

Business Insider Emails & Alerts Site highlights each day to your inbox. Email Address Join

Follow Business Insider Australia on Facebook, Twitter, LinkedIn, and Instagram.