They are seeing a common interest with Iran, the same tribal sheikh said.

Then they planted roadside bombs and destroyed the headquarters, said the tribal sheikh who declined to be named.

Among them were a police officer, an army official, the headmaster of a school, a Sunni tribal sheikh and his son.

Anbar clerics and hardline tribal sheikhs say that is not enough either.

Negotiations were underway involving local tribal sheikhs for a truce, the source said.

Army officers, presidential guard units, tribal sheikhs, clerics and politicians have defected to the opposition.

Even today, in some houses outside Baghdad, tribal sheikhs adorn their homes with pictures of the crown prince.

While the tensions have eased, Sunni tribal sheikhs in Anbar have complained they feel alienated by the central government.

For its part, Saudi Arabia provided "blatant" support to allied tribal sheikhs and parties in Yemen, he said.

By building strong relationships with Iraqis on the ground he convinced his military leaders at the Pentagon to work with the powerful tribal sheikhs.