U.S. military commanders are startled and worried by Baghdad's restrictive new reading of the U.S.-Iraqi security agreement, sources say.

Iraq's top military commanders told their U.S. counterparts in a July 2 directive they are strictly interpreting the agreement -- which stipulated that American troops leave Iraqi cities by June 30 -- to mean that American resupply convoys can only move at night, all joint patrols must end and remaining battalions can't help train Iraqis, The Washington Post reported Saturday.

Those restrictions are endangering U.S. forces because they have been unable to fully respond to an escalation of attacks by radical Shiite militia groups, an unnamed senior U.S. military intelligence official told the newspaper, adding that if the extremists realize "some of the limitations that we have, that's a vulnerability they could use against us."

The Iraqi orders are "contrary to the spirit and practice of our last several months of operations," Maj. Gen. Daniel Bolger, commander of the Baghdad division, wrote in an e-mail obtained by the Post.

Brig. Gen. Heidi Brown, who oversees logistical aspects of the American withdrawal, told the newspaper Iraqi and U.S. commanders have been ironing out differences in recent discussions.