On Tuesday, the GOP leader quietly invited Republican Sens. Ted Cruz of Texas, Lindsey Graham of South Carolina, John Cornyn of Texas and Mike Lee of Utah to his office to discuss strategy, according to people familiar with the meeting.

During the 30-minute session, Cruz pitched McConnell on the idea of witness reciprocity — if Democrats want to hear from former Trump national security adviser John Bolton on the Ukraine scandal, then Republicans get to hear from Hunter Biden. McConnell was open to that message, said a source familiar with the discussion. Cruz and Sen. Rand Paul (R-Ky.) later raised the strategy to the broader Senate Republican Conference.

Then shortly after, and echoing the message of Cruz and Paul, McConnell publicly warned Democrats that if they want to call additional witnesses during the proceedings, Republicans will counter with some of their own, and Democrats won’t like who’s on the GOP list.