"Both leaders expressed strong support for actions and agreed to join us in providing humanitarian assistance to Iraqis suffering so much," Obama told reporters at the White House after speaking by telephone with British Prime Minister David Cameron and French President François Hollande.
Thousands of Yazidi Kurds have received a second US airdrop of food and water as they seek refuge from the fear of genocide by militants with the Islamic State (IS) on the western edge of Kurdistan’s border with the rest of Iraq.
The humanitarian effort followed US airstrikes against fighters with IS, the first military intervention in the country since US ground troops withdrew at the end of 2011.
Obama, who authorised the use of force on Thursday, said US air strikes have destroyed arms and equipment used by the fighters and that there was no timetable for this fresh round of US involvement in the country.
"I'm not going to give a particular timetable, because as I've said from the start, wherever and whenever US personnel and facilities are threatened, it's my obligation, my responsibility as commander in chief, to make sure they are protected," Obama said to reporters.
On Friday, French President François Hollande said France was ready to participate in humanitarian efforts to end civilian suffering in Iraq and called for a meeting to convene with international partners.
"The international community cannot ignore the threat represented by the advance of this terrorist group for the local population, the stability not only of Iraq but of the whole region," Hollande said in a statement.