U.S. Democratic senator says still backs more Iran sanctions

By Patricia Zengerle WASHINGTON (Reuters) - A Democratic co-sponsor of a bill to impose new sanctions on Iran if there is no agreement on its nuclear programme by July said on Friday he stood by the legislation in the face of warnings that it could torpedo international negotiations. "All I'm saying is let us put in prospective sanctions that don't get imposed ... until July," Senator Robert Menendez said. Menendez was asked about Iran during an event in his home state of New Jersey after a join