OPEC WANTS 18 DLR OIL PRICE - OAPEC OFFICIAL OPEC believes world oil prices should be set around a fixed average price of 18 dlrs a barrel, OAPEC Assistant General Secretary Abdelaziz Al-Wattari said. In a speech to a European Community/OAPEC/OPEC seminar in Luxembourg released here, Al-Wattari said, "OPEC believes ...the world energy trade should be kept without restrictions and should be built around a fixed average price of 18 dlrs." Al-Wattari noted that total OPEC output was below the organization's agreed ceiling for all member countries in February, although this had meant sacrifices. The effect of these sacrifices meant that market stability, though restored to a good level, was still under pressure, Al-Wattari said. "A lasting stability in the world market requires a wider scope of international cooperation," he said.