The number of Sunni volunteers - many of them ex-insurgents - joining Iraq's security forces continues to swell despite an uneasy relationship with the Shiite-led government, a top U.S. commander said.

At the urging of the U.S., Prime Minister Nouri al-Maliki's government reluctantly committed to absorbing up to 20 percent of the nearly 100,000 members of the Sons of Iraq, also known as Awakening Councils, into the security services in a move toward reconciliation with the minority Sunni Arab community.

Army Lt. Gen. Lloyd Austin, the No. 2 U.S. commander in Iraq, said two months after the U.S. turned control of the Sons of Iraq over to the Iraqi government, there has been no indication that al-Maliki does not intend to honor his promise.

"Since we started this transition program, all I have heard is its not going to work," Austin told The Associated Press in an interview Thursday. "It will work. The government of Iraq wants it to work. The Sons of Iraq want it to work. Our leadership wants it to work."

The Iraqi government also has promised to pay the rest of the Sunni volunteers until it can find them civilian jobs. Many of them were former insurgents who battled U.S. and Iraqi troops before agreeing to work with American troops against al-Qaida.

U.S. officials fear some will return to the battlefield if the government does not honor its pledge.

The Iraqi government began last month paying the salaries of about 54,000 mostly Sunni fighters in Baghdad province. Monthly income is expected to be about $300, the same amount that the Americans paid.

But many Iraqi officials are openly contemptuous of the volunteers, fearing they may turn against the Shiites once the Americans leave.

Austin said he recognizes that deep suspicions remain, a concern that appeared to be addressed during a recent meeting at an Iraqi army base with Maj. Gen. Mizher Shakir Nasief, commander of the 11th Iraqi Army Division.

During the meeting observed by the AP, Austin asked how the Sons of Iraq were assimilating into the security forces.

"I tell my soldiers to treat them equally and get the benefit of their experience," Nasief said, adding that some of the Sunni soldiers recently provided intelligence that led to insurgent arrests in Baghdad.