BAGHDAD, IRAQ, SEPT. 14 -- Iraqi officials today told U.N. Secretary General Javier Perez de Cuellar that the U.N. Security Council should impose sanctions against Iran for failing to accept the United Nations' cease-fire order in the Persian Gulf war.

With Perez de Cuellar nearing the end of a tour aimed at moving Iran and Iraq toward accepting the truce call, western diplomats here suggested that prospects for progress were dim.

Iraqi President Saddam Hussein, quoted by Iraq's official news agency, accused Iran of having started the war. The U.N. secretary general had earlier met Iraq's foreign minister, Tariq Aziz, who said sanctions should be imposed because of Iran's refusal to yield to the international community's call for peace.

The question of who started the seven-year-old Persian Gulf war has become the major stumbling block to implementation of the Security Council's July 20 cease-fire resolution. Iran insists that Baghdad should be labeled the aggressor. During Perez de Cuellar's weekend visit to Tehran, Iranian President Ali Khamenei appeared to suggest a forum for condemning Iraq, telling the U.N. chief that the Nuremberg tribunal set up after World War II had set a precedent for trying war crimes.

But Iraq's President Saddam Hussein told Perez de Cuellar that "all facts prove -- by tangible evidence -- that the Iranian regime started aggression and war." Iraq repeated that it will accept the U.N. resolution only if Iran does the same.

{Near the mouth of the gulf, two U.S.-protected oil-tanker convoys passed each other today, one heading into the waterway and one leaving it, as the U.S. Navy took advantage of a lull in the tanker war, The Associated Press reported.

{The two convoys of reflagged Kuwaiti tankers passed within 1,500 yards of each other at midmorning, according to an AP press pool report from a Navy vessel.}

Iraq and Iran accused each other of breaking a tacit cease-fire during Perez de Cuellar's visit, but each denied that it had started any fighting.

Western diplomats said they believed Perez de Cuellar had come empty-handed from Tehran as Iran refused to back down on its key demand that Iraq be punished as the aggressor. The U.N. chief was expected to leave Baghdad on Tuesday. He will report back to the Security Council, which must then decide whether to push for an arms embargo to reinforce its resolution.

"There must come a point where the secretary general says: 'I have spoken to both sides, I have carried out my mission and I have come to the conclusion no progress is possible,' " said one diplomat.