In another sign that support for al-Jaafari is weakening within his coalition, Qasim Dawood, an independent member of the Iraqi legislature, on Saturday became the first member of the alliance to publicly call for al-Jaafari to withdraw his name for prime minister.

''I call on al-Jaafari to take a courageous step and set a fine example by stepping down,'' said Dawood, according to the Reuters news agency. ''We have stood behind him for 50 days, and today we have reached the conclusion that there should be a prime minister for all Iraqis, not just one group.''

A senior adviser to al-Jaafari, Adnan Ali Kadhimi, said no formal demand had been made for al-Jaafari to step down, and he would not do so. ''No one is saying, 'We are giving you an ultimatum,' '' Ali said. ''Dr. Jaafari is not going to kneel to the demand of this person or that person. He is the candidate of the alliance. He got the most votes.''

Violence continued across the country, meanwhile, with at least 20 people killed. The U.S. military said one of its helicopters had gone down southwest of Baghdad while on combat air patrol. The status of the crew was unknown, a military statement said.

Reuters reported that the Rashedeen Army, an insurgent group, said in an Internet posting that it had shot down a U.S. helicopter near the town of Yusufiyah, about 15 miles southwest of Baghdad, and that residents of the area had reported hearing gunfire. No further details were available.

In Germany, American journalist Jill Carroll disavowed comments she made in a video recorded the night before she was released from nearly three months in captivity in Baghdad. In the video, which her kidnappers posted on the Internet after Carroll, 28, was set free Thursday, she expressed support for the Iraqi insurgency and criticized the U.S. occupation.

But in a statement released Saturday by the Christian Science Monitor, her primary employer, Carroll said: ''Things that I was forced to say while captive are now being taken . . . as an accurate reflection of my personal views. They are not.''

Carroll called the people who kidnapped her and killed her translator on Jan. 7 ''criminals, at best. . . . They put me, my family and my friends - all those around the world who have prayed so fervently for my release - through a horrific experience. I was, and remain, deeply angry with the people who did this.''