Caroline Linton is an associate managing editor on the political team for CBSNews.com. She has previously written for The Daily Beast, Newsweek and amNewYork.

As the U.S. has been carrying out airstrikes against Venezuelan and Colombian vessels in the Caribbean and Pacific Ocean that the Trump administration has accused of carrying drugs and cartel members, Republican Sen. Lindsey Graham said Sunday that land strikes in Venezuela -- a significant escalation -- are a "real possibility."

"I think President Trump's made a decision that [Nicolas] Maduro, the leader of Venezuela, is an indicted drug, drug trafficker, that it's time for him to go, that Venezuela and Colombia have been safe havens for narco-terrorists for too long, and President Trump told me yesterday that he plans to brief members of Congress when he gets back from Asia about future potential military operations against Venezuela and Colombia," Graham said Sunday on "Face the Nation with Margaret Brennan."

Mr. Trump suggested last week that land strikes are "going to be next," saying on Thursday that "the drugs coming in by sea are like 5% of what they were a year ago" due to the strikes. Mr. Trump did not offer any evidence to back up this claim, and members of Congress have also said the administration hasn't provided sufficient evidence that the targeted vessels are carrying drugs.

As of Friday, at least 43 people have been killed in the U.S. strikes in the Caribbean and eastern Pacific that have occurred on 10 vessels since Sept. 2. Last week, the Colombian government called on the U.S. "to respect the norms dictated by international law" and cease the strikes.

Graham on Sunday said there will be a Congressional briefing on land strikes, not an invasion, although he also called for the removal of Venezuelan leader Nicolas Maduro. Graham repeatedly cited former President George H.W. Bush's invasion of Panama in 1989, saying the Bush administration didn't receive Congressional approval for that mission.

"Bush 41 went into Panama to replace the leadership there, because the Panama leadership, Panamanian leadership, were working with drug cartels to threaten our country," Graham said.

Although the U.S. Constitution grants Congress the sole authority to declare war, Graham repeatedly said he is confident the Trump administration has the authority to carry out the strikes. Democrats and even some Republicans have criticized the White House's action.

"To the other senators, you deserve more information, and you're going to get more information, but there is no requirement for Congress to declare war before the commander-in-chief can use force," Graham said. "Panama and Grenada are two examples in our backyard, where Republican presidents chose to go after countries and leaders that were threatening our people."

Democratic Sen. Ruben Gallego of Arizona said Sunday on NBC's "Meet the Press" that the Trump administration's actions in the Caribbean are "murder."

"If this president feels that they're doing something illegally, then he should be using the Coast Guard," Gallego said. "If it's an act of war, then you use our military, and then you come and talk to us first. But this is murder. It's sanctioned murder that he is doing."

Graham pushed back against Gallego's remarks, saying on Sunday that "this is not murder. This is protecting America from being poisoned by narco-terrorists coming from Venezuela and Colombia."

Sen. Lindsey Graham says land strikes in Venezuela are a "real possibility" amid rising tensions