But it wasn't clear if Rizgar Mohammed Amin's resignation had been accepted amid behind-the-scenes efforts to change his mind.
Amin is the head of a five-judge tribunal overseeing the case against Saddam and seven co-defendants for the deaths of more than 140 Shiite Muslims in the town of Dujail in 1982 in retaliation for an assassination attempt.
The chief prosecutor in Saddam's trial, Jaafar al-Mousawi, told The Associated Press that Amin's resignation — if accepted — would not affect the proceedings because he could be quickly replaced.
"There are substitutes. If any judge wanted to resign it wouldn't hinder the trial process," he said.
Amin would be the second judge to step down in the case. Another member of the panel recused himself in late November because one of the co-defendants may have been involved in the execution of his brother. That judge was replaced.
In other developments:
A court official, speaking on condition of anonymity because of the sensitivity of the case, said Amin had offered to resign but efforts were under way to get him to reverse the decision.
The U.S. military, meanwhile, said a Marine was killed Friday by small-arms fire during combat in the western town of Ramadi, raising to at least 2,215 the number of American troops who have died since the Iraq war started in March 2003.
Electoral officials also said results from the Dec. 15 parliamentary vote could be certified by next week after repeated delays, opening the way for negotiations to formally get under way for the formation of a broad-based coalition government.
In the Saddam case, the chief judge — who is the only one of the five to be identified publicly due to security concerns — has been dismayed by the way he had been attacked in the media by critics who said he allowed the proceedings to get out of hand, the official said.
Saddam has often grabbed the spotlight during the nearly three-month-old trial. He has railed at the judge, refused to show up at one session, claimed he was tortured and openly prayed in court when the judge would not allow a recess.
Since the trial opened on Oct. 19, two defense lawyers also have been assassinated and a third has fled the country. Police also uncovered a plot to fire rockets at the courtroom in late November.
U.S. Senate Judiciary Chairman Arlen Specter, R-Pa., met with Amin in late December and told him to take stronger control of the proceeding.
Amin is a Kurd who before the Saddam trial was virtually unknown outside his home region.
The trial is scheduled to resume Jan. 24 after a monthlong recess. The defendants could face death by hanging if convicted.
Senior Iraqi election official Safwat Rashid said certified results from Iraq's contested elections could be released within a week. But he said that if any further complaints were received, it could take an additional 10 days to get final results.
Rashid and other officials said they were expecting a group of assessors from the International Mission for Iraqi Elections, or IMIE, to issue a preliminary report on the results Sunday or Monday.
An IMIE official, Mazin Shuaib, confirmed an interim report would be issued within days but said the team's final report would take about another week.
The assessors said they would release full uncertified results shortly after the report. Political parties and groups will then have time to file further complaints.
"There will be two days to receive the complaints from the political entities and the concerned parties," general director of Iraq's elector commission, Adel al-Lami, told Pan-arab Al-Arabiya television. "It will take another two days to look into these complaints, and then decide whether they are accepted or rejected."
He said if the complaints are accepted it "will take 10 days to respond."
Final election results have been delayed by Sunni Arab complaints of fraud. Although leading politicians have expressed hopes a government could be formed in February, most experts and officials agree it could take two to three months, as it did after the January 2005 elections for an interim government.
The governing United Iraqi Alliance, a Shiite religious bloc, has a strong lead, according to preliminary results. But it won't win enough seats in the 275-member parliament to avoid forming a coalition with Sunni Arab and Kurdish parties.