WASHINGTON (AFP) - The United States is ready to make further air drops in Iraq after US planes on Thursday flew in food and water for some 8,000 beleaguered minorities, an official said.

"If it becomes necessary, we will do another drop," a US official told reporters on condition of anonymity.

Another official, briefing reporters after President Barack Obama announced the action, said that United States expected the trapped Yazidi minorities to need further outside support.

"I would expect that need to continue," he said.

But the second official said that other nations, including Iraq, may be able to carry out future air drops.