(CNN) -- President Barack Obama exhorted Iraqi leaders to come up with a political solution to governing their nation because "if they don't, there won't be a military solution to the problem," he told CNN in an interview Friday.
Obama wants to see Iraq create a command structure that includes Shiites, Sunnis and Kurds, which are the country's chief groups, he told CNN's Kate Bolduan.
"We gave Iraq the chance to have an inclusive democracy," Obama said on the eve of U.S. military advisers arriving in Iraq to help the government besieged by militant extremists.
Sunni militants have crossed over from northern Syria to blitz major Iraqi cities. Hundreds of thousands of civilians have fled from their path, creating a new refugee and political crisis.
The militants, called the Islamic State in Syria and Iraq, are an al Qaeda splinter group. Supported by many Sunni factions, the ISIS fighters continue their fierce advance in Iraq, threatening Baghdad.
Senior U.S. officials say the Obama administration is of the belief that Prime Minister Nuri al-Maliki is not the leader Iraq needs to unify the country and end sectarian tensions. His government is dominated by Shiites.
The first of up to 300 U.S. military advisers will arrive in Iraq as soon as Saturday, a senior defense official told CNN on Friday.
This first group from outside Iraq is expected to be very small, the official said.
Meanwhile, some U.S. military personnel already in Iraq at the security cooperation office in the U.S. Embassy in Baghdad will be reassigned and become the first of the advisers to go to work, Pentagon press secretary Rear Adm. John Kirby said.
The first group of advisers will begin work by conducting an initial assessment of Iraqi troop capabilities and on what may be needed for a larger group of U.S. advisers, including additional security measures where they may be deployed, a senior defense official said Friday.
The Pentagon has identified two preliminary locations in Baghdad and northern Iraq for proposed joint Iraq-U.S. operations centers, but those locations are not being disclosed because of security concerns, the official said.
The United States withdrew its final troops from Iraq at the end of 2011, nearly nine years after leading the invasion that ousted longtime leader Saddam Hussein.
On Friday, fierce fighting continued between suspected ISIS fighters and Iraq security forces and their recruits in northern and northeastern Iraq, with casualties on both sides.