DUBAI, UNITED ARAB EMIRATES, SEPT. 16 -- Iraq said its war planes resumed strikes on Iranian targets today, only hours after U.N. Secretary General Javier Perez de Cuellar left Baghdad at the end of his four-day mission to the region.

Iran, in turn, said its forces had attacked Iraqi naval targets in the northern Persian Gulf. It also announced that it would hold a new round of maneuvers in the Gulf of Oman starting Thursday in the region where French mine sweepers already have begun operations. Iran also said Kurdish forces which it backs were holding their own against counterattacks in northern Iraq close to strategic oil pipeline facilities.

The announcements signaled a renewal of the sea and land attacks that marked the weeks leading up to Perez de Cuellar's trip to Tehran and Baghdad, during which he sought to find grounds for implementing a Security Council resolution calling for a cease-fire in the long-running gulf conflict.

An Iraqi military communique said that its planes struck the eastern jetty of Iran's Kharg Island oil terminal at 3 a.m. and that a "large naval target," the Iraqi term for a ship, was hit an hour later near the Iranian coast. Later in the day, Baghdad reported strikes on the Iranian oilfields at Karang and Baghi-Malek. The Iraqis also said Iran had continued shelling the Iraqi city of Basra.

Iran, which previously has conducted naval maneuvers, said the new round would include speedboats equipped "with all sorts of light and medium-weight weapons" and would involve regular troops and Revolutionary Guards.

The announcement said the maneuvers were designed to train for "inflicting blows on global arrogance" of the western powers that have amassed a large fleet of warships in the Persian Gulf and in the Gulf of Oman just outside the gulf.

The Kuwaiti tanker Gas Prince, flying the American flag and escorted by U.S. warships, was reported to be approaching Kuwait's Ahmadi oil terminal after a quiet trip through the gulf.

French mine sweepers began working Friday in waters off the United Arab Emirates' port of Fujayrah, where two ships have struck mines believed to have been laid by the Iranians. British mine sweepers also are believed to be close to the area.

Western diplomats in the area have said they expect a full-scale renewal of hostilities now that Perez de Cuellar's mission is completed. They also have expressed fears of the conflict spilling over to envelop western warships that might get caught up in the fighting by accident.

In its version of today's military action, Tehran radio said tonight that Iran's Air Force had struck several Iraqi small naval craft in the northern gulf and also had hit coastal artillery positions.

Most recent air activity in the gulf conflict has involved the Iraqi Air Force, since Iran's air wing, mostly supplied by the United States during the days of the late shah, is grounded for lack of spare parts.