"What is lacking in Iraq now is the buy-in of all Iraqis into this new political system," Khalilzad said in an interview with CNN on 1 August in Baghdad.
"I'm prepared to help in any way I can to facilitate. I have told them that I'm available at any time if they need my help."
Khalilzad said that the constitutional drafters have indicated they will not seek an extension beyond the 15 August deadline.