The U.S. Democratic Party's presumed presidential nominee, Barack Obama, says Hillary Clinton was a "tough" and "outstanding" rival candidate for the party nomination.
Obama made the comment during a town hall meeting in the southeastern state of Virginia on Thursday.
Senator Clinton has promised to end her bid for the White House and rally her supporters behind Obama.
In a statement today, Clinton says her differences with the Illinois senator are small compared to those with Senator John McCain, the presumptive Republican nominee. Clinton is expected to formally endorse Obama on Saturday.
Obama secured enough delegates to secure the nomination Tuesday, making him the first African-American to clinch the presidential nomination for a major U.S. party.
Clinton, who sought to be the country's first female president, has expressed interest in becoming Obama's running mate. However, Obama told NBC News he is not going to rush into a decision.