South Carolina Sen. Lindsey GrahamLindsey Olin GrahamOcasio-Cortez: By Lindsey Graham's 1999 standard for Clinton, Trump should be impeached Senate votes to end US support for Saudi war, bucking Trump Former FBI official says Mueller won’t be ‘colored by politics’ in Russia probe MORE (R) said Wednesday he would lead a charge to investigate Russia's interference in the U.S. election and hacks on the Democratic Party.

"I think [Donald] Trump should take a real tough tone with Russia, because if he doesn't, you're going to allow Russia to begin to break apart alliances," Graham told CNN's Manu Raju.

The Republican senator also said he hoped to use his leadership role on two subcommittees to launch a deeper investigation of Russia's hacks, CNN reported. Graham chairs the State, Foreign Operations and Related Programs subcommittee and the Crime and Terrorism subcommittee.

Raju said Graham told him that he and Sen. John McCainJohn Sidney McCainTrump will likely win reelection in 2020 Kevin McLaughlin tapped to serve as NRSC executive director for 2020 Kasich on death of 7-year-old in Border Patrol custody: 'Shame on Congress' MORE (R-Ariz.), chair of the Armed Services Committee, will travel to Eastern Europe to investigate Russian meddling in other countries' elections.

During the campaign, Graham was a strong GOP critic of Trump, including on his friendlier stance toward Russia, and chose to vote instead for independent candidate Evan McMullin.