A Republican witnesses from the House impeachment inquiry will join the Senate Republican lunch on Tuesday.

Jonathan Turley, who testified during a House Judiciary Committee hearing last week, will take part in the closed-door caucus lunch, a source familiar confirmed to The Hill.

The lunch comes as senators are ramping up their efforts to prepare for a likely impeachment trial in the Senate, which is expected to start as early as January. GOP senators had lunch last week with White House counsel Pat Cipollone.