WASHINGTON -- US President Donald Trump threatened Friday that Cuba is going to "fall pretty soon," but his administration will focus on the ongoing war with Iran "right now."

"They want to make a deal, and so I'm going to put Marco (Rubio) over there and we'll see how that works out," Trump said, referring to the US secretary of state, in a phone interview with CNN.

"We're really focused on this one right now. We've got plenty of time, but Cuba's ready -- after 50 years," he added.

On Thursday, Trump said that it's only a "question of time before" people go back to Cuba.

Cuba has been facing a severe economic and energy crisis since the United States forcibly seized Venezuelan President Nicolas Maduro on Jan 3 and heavily disrupted Cuba's oil supplies from Venezuela and Mexico.

The United States and Israel have intensified their joint military attacks on Iran launched on Feb 28, which killed Iran's Supreme Leader Ayatollah Ali Khamenei, along with senior military commanders and civilians.