Zalmay Khalilzad, the plainspoken dealmaker and Republican party insider who has won praise and criticism for attempts to broker Sunni political participation in Iraq's fragile government, is likely to quit his post as US ambassador in Baghdad in the coming months, a senior Bush administration official said Monday. As the congressional elections approached in the United States, Khalilzad has been a public face of Bush administration attempts to project both willingness to change strategy or tactics in an unpopular war and solidarity with the increasingly fractious Shi'ite-led government of Prime Minister Nouri al-Maliki. Khalilzad's departure has been rumored for months, but he has not turned in his resignation, the State Department official said. The official spoke on condition of anonymity because neither the White House nor Khalilzad has announced any personnel changes. Khalilzad could leave as soon as the end of this year, but is more likely to remain in his post through the spring, the official said. "He doesn't want to stay there forever and there are ongoing discussions about when he will finish his time, but there is no definite date," the official said.