Move comes as partial shutdown prospect still looms.
President Trump issued an executive order Tuesday evening closing federal offices and excusing employees from duty on Dec. 24.
Under the order, "the heads of executive departments and agencies may determine that certain offices and installations of their organizations, or parts thereof, must remain open and that certain employees must report for duty on December 24, 2018, for reasons of national security, defense, or other public need."
Presidents historically have granted civil servants an extra vacation day on Dec. 24 when Christmas falls on a Tuesday, to make a four-day weekend. President Obama gave federal employees Christmas Eve off in 2012, the most recent year in which Christmas was on a Tuesday; President George W. Bush did the same in 2007 and 2001.