President Obama will offer his formal endorsement of Hillary Clinton with a video to be released later on Thursday and plans to campaign with the former secretary of state in Wisconsin next week, according to two sources familiar with the plans.

The swift endorsement comes after the president met with Sen. Bernie Sanders at the White House earlier Thursday as the Vermont senator mulls his options about exiting the Democratic nominating battle.

Sanders is under pressure to stand down and help to unify the party after a long and contentious battle with Clinton for the nomination. Obama’s endorsement will add to that pressure, although most party leader, including the president, have urged that he be allowed to decide on his future plans on his own timetable.