U.N. efforts to break the stalemate in Persian Gulf peace talks appeared to have failed on Tuesday as Iraq's foreign minister cut short his visit to the United Nations and prepared to return to Baghdad. There was no immediate word if or where negotiations between Iran and Iraq, under the auspices of Secretary General Javier Perez de Cuellar, would be resumed. Iraqi Foreign Minister Tareq Aziz wanted the talks to continue in Geneva, where they were adjourned Sept. 13, stalled over guarantees for gulf shipping and the reopening of the Shatt al-Arab, the waterway that forms part of the Iran-Iraq border and is Iraq's main access to the gulf. But the Iranian side preferred a transfer to New York.