Washington (CNN) A leading Republican lawmaker is calling for investigations into alleged Russian cyberhacks during the US election despite President-elect Donald Trump's repeated calls for warmer ties with Moscow.

Sen. Lindsey Graham, a South Carolina Republican and one of the chamber's most experienced foreign policy hands, said the attempt by a foreign country to interfere with the US voting process needs better understanding and a vigorous response.

"Assuming for a moment that we do believe that the Russian government was controlling outside organizations that hacked into our election, they should be punished," Graham told reporters Tuesday. Referring to Russian President Vladimir Putin, Graham added that, "Putin should be punished."

Graham, who wants the hearings to examine all Russia's "misadventures throughout the world," has the support of colleagues on both sides of the aisle. As other Republicans issued warnings about Russian activities, the hearings could become a source of tension between the GOP and the new President.

"You could see, going forward, a Congress that's really at loggerheads with the White House on policy toward Russia," said Angela Stent, director of the Center for Eurasian, Russian and East European Studies at Georgetown University.

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