Niagara Falls, Ontario ? The U.S. on Saturday refused to accept hard-line President Mahmoud Ahmadinejad’s claim of a landslide re-election victory in Iran and said it was looking into allegations of election fraud.

Any hopes by the Obama administration of gaining a result similar to Lebanon’s recent election, won by a Western-backed moderate coalition, appeared to be in jeopardy.

“We are monitoring the situation as it unfolds in Iran, but we, like the rest of the world, are waiting and watching to see what the Iranian people decide,” U.S. Secretary of State Hillary Rodham Clinton said at a news conference with Canada’s foreign affairs minister, Lawrence Cannon.

Minutes after Clinton spoke, the White House released a two-sentence statement praising “the vigorous debate and enthusiasm that this election generated, particularly among young Iranians,” but expressing concern about “reports of irregularities.”

Despite the challenge from reformist Mir Hossein Mousavi to incumbent Ahmadinejad, many officials and experts thought a Mousavi victory would result in only incremental shifts toward the U.S.