Washington — Senate Democrats on Tuesday tried to force a vote on a measure to prevent President Trump from launching a military attack on Cuba, as he repeatedly threatens action against the island. 

But Republicans blocked the procedural vote from moving forward, arguing that the U.S. isn't engaged in hostilities with Cuba. The issue is "moot," GOP Sen. Rick Scott of Florida said. 

Democrats are seeking to get ahead of the president on Cuba after he took unilateral action against Venezuela and Iran.

The resolution was introduced in March by Democratic Sen. Tim Kaine of Virginia, who has also spearheaded the efforts in the Senate to rein in Mr. Trump on Venezuela and Iran. More than half a dozen votes related to military action in those countries have yielded similar results, with most Republicans voting down restrictions on military action and defending the president's broad authority to use military force. 

"I've never heard the suggestion that Cuba poses an imminent security threat to the United States," Kaine said on the Senate floor ahead of the vote. 

Since the U.S. military captured Venezuelan President Nicolás Maduro in January, Mr. Trump has warned that he has had his sights set on Cuba. He has said that he believed he would have "the honor of taking Cuba" and that "Cuba's going to be next." 

Earlier this month, Mr. Trump said military action against Cuba is still on the table. 

"We may stop by Cuba after we're finished with this," he said, referring to the Iran war. 

Secretary of State Marco Rubio has been more direct about the administration's possible goals in Cuba, testifying to Congress in January that "we would love to see the regime there change." He said it would be of "great benefit" to the U.S. and has also called for economic reforms. The administration has said it is looking to resolve its concerns with Cuba through diplomacy, but has not ruled out some kind of military action.

Kaine argued the U.S. is already engaged in hostilities with Cuba, citing the Trump administration's oil blockade on the island that has had devastating effects on civilians. Kaine said the U.S. would consider the blockade an act of war if the tables were turned. 

"The U.S. is using force to block energy from going to Cuba," he said. 

Cuban leadership has said the country is ready to fight any U.S. aggression. 

As tensions remain high, the two countries have engaged in diplomatic talks. A delegation of senior State Department representatives traveled to Cuba earlier this month, marking the first time a U.S. government plane has landed in Cuba since President Barack Obama traveled to the island in 2016. 

A State Department official told CBS News that Mr. Trump is open to resolving the United States' concerns through diplomacy, but he "will not let the island collapse into a major national security threat if Cuba's leaders are unwilling or unable to act."