Pentagon press secretary Geoff Morrell said Tuesday that if Congress does not pass the $1.8 billion Global War on Terror (GWOT) supplemental, the U.S. Army will be unable to pay troops in mid-June and may be forced to make a reprogramming request that would borrow from Navy and Air Force payroll funds.

Secretary of Defense Robert Gates wrote letters to members of Congress Monday encouraging them to pass the supplemental by Memorial Day, or money to pay Army troops will run out by June 15.

According to Morrell, Gates asked that Congress be kept apprised of Army contingency planning if the supplemental isn't passed in time. Last November and December, similar urgency over passing the supplemental focused on the Operations and Maintenance (O&M) budget, which Morrell said is "more robust" than payroll this time around, "but not by much.