WASHINGTON (Reuters) - President Barack Obama said on Monday it was not "out of bounds" for his re-election campaign to push Republican presidential challenger Mitt Romney to release more tax returns, saying such transparency is what the American people would rightly expect.

Obama made the comments in the White House press briefing room. He said the precedent for candidates to release years of tax returns was set decades ago and should not change.

(Reporting by Laura MacInnis and Matt Spetalnick; Editing by Will Dunham)