Iraq's security forces must develop intelligence, battlefield medicine and logistics before they can stand on their own, the No. 2 U.S. commander in Iraq said.

In the rush to create a security force to guard Iraq against violence from insurgents, the U.S. military has been providing the support networks needed to help the country's forces before the Americans leave by the end of 2011.

Lt. Gen. Lloyd Austin, commander of all ground forces in Iraq, said U.S. troops now have to partner with Iraqis and work with them on a daily basis to provide the necessary additional training.

"Our intent is to make sure we have helped the Iraqis to have the right capacity, the right capability to handle the insurgent activity when we leave," Austin told The Associated Press during an interview Thursday in his office at the Faw Palace, headquarters of Multi-National Corps Iraq.

U.S. forces will be operating under a new security agreement on Jan. 1 that gives Iraqi authorities a role in approving and overseeing U.S. military operations.

It replaces a U.N. mandate that gives the U.S.-led coalition sweeping powers to conduct military operations and detain people without charge if they were believed to pose a security threat. The new pact requires that U.S. troops withdraw from Baghdad and other cities by the end of June and leave the country entirely by Jan. 1, 2012.

Austin said American troops began the transition months ago, conducting more and more joint operations with Iraqi forces. "The reason we are doing them is that we knew this was coming many months ago," he said.

In 2006, U.S. forces attempted to hand over security in portions of Iraq to security forces only to have them collapse under the weight of sectarian violence and insurgent attacks.

Iraqi forces are now responsible for security in 13 of the 18 provinces with coalition forces available for help if requested.

Austin said U.S. forces are moving as fast as possible to get the Iraqi security forces to a capable and competent level, but cautioned progress would take time.

"We are in no hurry to race away and have things crumble on us," he said.

U.S. and Iraqi officials acknowledge that the capabilities of Iraqi security forces have been improving, but privately doubts persist about whether they have the support and discipline to succeed.

Austin acknowledges the security gains are fragile, citing recent flare-ups of insurgent activity in Baghdad, Basra and other parts of southern Iraq.

"We are still fighting a fairly significant fight against al-Qaida in the north," he said.

Austin said the Iraqi force will naturally develop at an uneven pace, saying some units are older and more seasoned than newer units that are just being created.

He also said the forces need to acquire specific weapons and vehicles, and then need to get experience with those items.