United Nations Secretary-General Antonio Guterres strongly condemned attacks on two oil tankers on Thursday in the Gulf of Oman that left one ablaze and both adrift, warning that the world cannot afford "a major confrontation in the Gulf region."

"I strongly condemn any attack against civilian vessels. Facts must be established and responsibilities clarified," he told a meeting of the U.N. Security Council on cooperation between the United Nations and the League of Arab States.

The attacks were the second in a month near the Strait of Hormuz, a major strategic waterway for world oil supplies.

The United States and Saudi Arabia blamed Iran for last month's attacks using limpet mines on four tankers off the coast of the United Arab Emirates, a charge Tehran denies.

Arab League Secretary-General Ahmed Aboul Gheit called on the U.N. Security Council to act against those responsible to maintain security in the Gulf region.

"Some parties in the region are trying to instigate fires in the region and we must be aware of that," he told the 15-member council, without specifically naming anyone.