Republicans in the U.S. House of Representatives on Thursday added $5 billion to a government spending bill to help President Donald Trump make good on a pledge to build a border wall, a move that made a partial federal government shutdown more likely this weekend.

The Senate is highly unlikely to pass the legislation, which funds agencies responsible for federal law enforcement activities, airport security screenings, space exploration, and farm programs, by a midnight deadline on Friday.

Trump had said he would not sign a Senate-passed bill to keep the government running through Feb. 8 because it lacked funds for the wall, a signature promise of his 2016 run for office, so Republicans in the House of Representatives scrambled to add money to appease the president.

Trump demanded $5 billion to put toward a wall on the U.S. border with Mexico that he argues is needed to keep out illegal immigrants and drugs, a down payment on a massive project which Democrats have rejected as ineffective and wasteful.

The funding uncertainty weighed on markets on Thursday but it was later dwarfed by another bombshell from the Trump administration: the resignation of Defense Secretary Jim Mattis.

Read more in Reuters.