"For the sake of America’s national security and that of our allies, I hope President Trump will put an end to this speculation and reject such a reckless course," McCain said in a statement Friday. "If he does not, I will work with my colleagues to codify sanctions against Russia into law."

Trump is scheduled to speak with Russian President Vladimir Putin on Saturday, the first time the two men will talk on the phone since last week's inauguration.

Top Trump adviser Kellyanne Conway told Fox News on Friday morning that lifting sanctions on Moscow was "under consideration."

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Any move to lift sanctions would likely spark bipartisan backlash on Capitol Hill.

McCain added Friday that Trump should remember that the previous three administrations had "high hopes" for bettering the U.S.-Russian relationship and failed because "Putin wants to be our enemy."

“[Trump] should remember that the man on the other end of the line is a murderer and a thug who seeks to undermine American national security interests at every turn," he added. "For our commander-in-chief to think otherwise would be naïve and dangerous.”

McCain outlined on Friday why he believes Trump should oppose lifting sanctions, including Moscow's support for Syrian President Bashar Assad, invading Ukraine, and Putin's push for NATO to reduce its presence in eastern Europe.