The Iraqi High Tribunal has dropped all charges against Saddam Hussein, who was hanged on 30 December, as the genocide trial of six co-defendants resumed.
Saddam Hussein was executed on 30 December
They are charged with crimes against humanity over a campaign against Kurds in the 1980s that left 100,000 dead.
Saddam Hussein was hanged after an earlier trial over the killing of 148 Shia Muslims in the town of Dujail.
Many Kurds were disappointed that he was executed before facing justice for his role in the Anfal campaign.
Among the six remaining defendants is Saddam Hussein's cousin, Ali Hassan al-Majid, sometimes known as "Chemical Ali" for his alleged use of chemical weapons against the Kurds.
As the trial resumed he tried to read a prayer from the Koran in memory of his cousin, but the judge ordered him to stop.
The prosecution then played a video, allegedly containing the voice of Mr Majid threatening to bomb the Kurds.
"I will attack them with chemical weapons," the voice said.
The tape also showed pictures of dead men, women and children.
The defence argues the campaign - codenamed al-Anfal, or "the spoils of war" - was a legitimate operation to quell a rebellion after some Kurds sided with the enemy during the Iran-Iraq war.
In other developments:
- President George W Bush is due to name US ambassador to Iraq Zalmay Khalilzad as the country's new envoy to the UN
- Mr Bush's long-awaited address on a new strategy in Iraq is scheduled for Wednesday, officials say
- Violence on the ground continues, with at least nine people killed in an ambush on a bus carrying workers to Baghdad airport.
Executions 'this week'
The Baghdad trial had been in recess since 21 December.
Its resumption throws the spotlight back on the Iraqi judicial system which has come under international criticism for the handling of Saddam Hussein's execution.
Ali Hassan al-Majid wore a beard as a sign of mourning for his cousin
The former leader was taunted at the gallows and illicit images of his execution later appeared on the internet.
The UN has called for a stay of execution for two others sentenced to death in the Dujail trial.
But the Iraqi government says the execution of Barzan al-Tikriti and Awad al-Bandar will take place this week.
A lawyer for the two defendants said that they had told they were going to be hanged along with Saddam Hussein on 30 December.
The lawyer, Issam Ghazawi, said this was "torture" and that waiting for death was "more difficult that death itself".
Correspondents say the Iraqi government, dismissed by growing numbers of Iraqis as weak and ineffectual, is keen to push these executions through in order to prove its strength.
Keen to assert his independence, a spokesman for Iraqi Prime Minister Nouri Maliki on Monday said any political objectives announced this week by the White House will have come from Baghdad, not Washington.
President George Bush is to due to set "benchmarks" for political reform following widespread calls in Washington for a strict timetable of political progress to be imposed on their Iraqi partners.