WASHINGTON (Reuters) - Vice President Joe Biden on Wednesday said Iran would be held accountable for an alleged plot to assassinate the Saudi Arabian ambassador in Washington and that the Obama administration is working to unite world opinion behind a possible U.S. response.

"It is an outrageous act where the Iranians are going to have to be held accountable," Biden told ABC's "Good Morning America" program.

(Reporting by David Morgan; Editing by Eric Walsh)