No US air strikes yet in Iraq: Official

WASHINGTON - The United States has not carried out any air strikes in Iraq but is ready to do so after orders from President Barack Obama, an official said Thursday.

"No air strikes have taken place at this time, but we remain postured to take targeted military action should the situation warrant it," the US official said on condition of anonymity.

Another official, briefing reporters after Obama warned of the risk of "genocide" against Iraqi minorities, said that the United States would act Islamist guerrillas threaten the key city of Arbil.

The official also said that the United States was prepared to take military action to "relieve the pressure" against the beleaguered Yazidi minority if Iraqi efforts do not work.

But the official said that the United States was not planning a "sustained campaign" against the extremists in the Islamic State movement, saying that Iraq bore the responsibility.