Washington (CNN) Sen. John Kennedy told Russian government officials to "stop screwing with our election" on a congressional visit to Russia last week, the Louisiana Republican told CNN on Monday.

Speaking on CNN's "At This Hour with Kate Bolduan," Kennedy said he warned Russian Foreign Minister Sergei Lavrov that Congress will "double down on sanctions ... if you screw with the elections this fall."

This was despite Lavrov's denial of any Russian interference with elections, which Kennedy "expected."

Even though Kennedy thought Lavrov to be a "bully" and "belligerent," the senator thought his message "was delivered."

"I went (to Russia) to ... deliver a message ... to the foreign minister, to the speaker of the house, and to a number of their senators," he said.

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