President Barack Obama formally endorsed Democrat Hillary Clinton for president via a video message Thursday afternoon.

Obama met with Democratic runner-up Sen. Bernie Sanders Thursday morning, paving the way for Obama to make a public endorsement of his former secretary of state. Sanders made a statement after his meeting with Obama, saying he would stay in the race through the D.C. primary Tuesday, and that he would work with Clinton to defeat Republican presidential candidate Donald Trump.

Clinton responded immediately to Obama's endorsement via Twitter.

Ahead of the final primary of the season in the District of Columbia, Clinton has 2,768 total delegates, including 572 superdelegates, compared to Sanders with 1,866 total delegates, and 47 superdelegates, securing her position as the presumptive Democratic presidential nominee.

Obama will begin campaigning with Clinton next week in Wisconsin.

Obama is also expected to increase his attacks on Trump, outlining why he feels the business tycoon is unfit to be president.  Trump responded to Obama's endorsement via Twitter.