The team, which has an office in the Jordanian capital, Amman, said in a statement on Saturday that the man attacked Saddam and that the two exchanged blows during a hearing attended by defence lawyer Khalil Dulaimi.
"As the president stood to leave the courtroom one of those present attacked him and there was an exchange of blows between the man and the president," the statement said.
The head of the tribunal did nothing to stop the assault, the statement alleged.
It did not say whether Saddam was hurt.
US denies incident
However, a spokeswoman for detainee operations in Iraq, the US military unit charged with overseeing the custody of prisoners including Saddam, said no such incident took place.
"Nothing like that happened with Saddam whatsoever," Lieutenant Kristy Miller said.
The US military is in charge of Saddam's custody,
although he is in Iraqi legal custody. Miller said that as far
as she knew Saddam almost never leaves US military sight.
Officials at the Iraqi Special Tribunal, the court set up to try the former president and other senior members of his now-
defunct Baath Party, were not reachable for comment.
Because of the alleged incident, the defence team said it would boycott the tribunal or any committee interrogating Saddam until he was given the right to proper legal representation by a team of international lawyers.
Sunni official sacked
A top Sunni official, who has been instrumental in urging Sunni Arabs to join the political process, has been fired, the prime minister's office confirmed on Saturday. The official said he was sacked for "speaking out against unjustified practices against Sunnis".
Adnan al-Dulaimi was dismissed on 24 July as head of the Sunni Endowment, the government agency in charge of the upkeep of Sunni mosques and shrines.
"I think that the reason behind my dismissal is that they want to silence a voice that is speaking against unjustified practices against Sunnis such as arrests, torture in the prisons, and also for my calls to release innocent detainees and to save Iraq from sectarianism, insecurity and divisions," al-Dulaimi said.
"They wanted to keep me away from this important post
from which I can defend our Sunni people," al-Dulaimi said.
On Saturday, Prime Minister Ibrahim al-Jaafari's office confirmed the dismissal but declined to speak further on the matter.