(CNN) Secretary of State Rex Tillerson warned that any Russian interference in November's midterm elections would "invite consequences," but suggested the United States is still vulnerable to such meddling.

"Well, I don't know that I would say we're better prepared (than in 2016) because the Russians will adapt as well," Tillerson told Fox News in an interview from, Bogota, Colombia Tuesday. "The point is if it's their intention to interfere, they're going to find ways to do that."

"And we can take steps we can take, but this is something that, once they decide they're going to do it, it's very difficult to preempt it," he said.

Tillerson said the Trump administration is seeing signs of meddling in European elections, as well as elsewhere in the Western Hemisphere, and suggested they could try to interfere in the upcoming US elections as well.

"I think it's important we just continue to say to Russia, 'look, if you think we don't see what you're doing, we do see it,'" said Tillerson. "'You need to stop. If you don't, you're going to just continue to invite consequences for yourself.'"

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