Senate Majority Leader Mitch McConnell has some advice for the president of the United States: Lay off the Republican senators who may determine your fate in an impeachment trial.

POLITICO reported McConnell, a Kentucky Republican, warned President Donald Trump at a private meeting in the White House last week to stop attacking senators during a discussion about the impeachment inquiry.

McConnell reportedly warned Trump explicitly to stop attacking Sen. Mitt Romney (R-Utah), whom he recently called a "pompous 'ass'" in a tweet after Romney said it's "wrong and appalling" for the president to urge foreign governments to investigate Democratic presidential candidate Joe Biden.

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Trump appears to have listened to McConnell's advice, according to POLITICO. The two leaders reportedly have conversations "all the time," even more so as the impeachment threat continues.

The House voted Thursday to approve a resolution mapping out rules for public hearings in the investigation, its first vote on the formal impeachment inquiry after House Speaker Nancy Pelosi (D-CA) declared an inquiry Sept. 24.

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Christal Hayes and Bart Jansen with USA Today contributed reporting.