Merchant ships carrying oil and other cargo continue to ply the southern Persian Gulf despite earlier fears that they would be caught in the cross-fire of war.

Chris Horrocks, secretary-general of the International Chamber of Shipping, estimates that more than half of the ports in the southern gulf are trading normally."After the initial tremors and concerns, it's certainly better than might have been expected," he said Wednesday.

Horrocks said the risk to commercial shipping has turned out to be minuscule largely because the Iraqi air force has been grounded by the war and because Iraqi targets include allied warships, not commercial vessels.

The danger is in the northern half of the gulf, beginning at Jubail, Saudi Arabia, according to the International Chamber of Shipping.

Most merchant ships are staying out of those waters, and Horrocks said the chances of hitting a mine in the south are remote.