Mr Aziz served as foreign minister and deputy prime minister under Saddam
An Iraqi court has opened a new trial against two members of Saddam Hussein's regime on charges of persecuting political opponents while in power.
The two defendants are Saddam's foreign minister, Tariq Aziz and the dictator's cousin, Ali Hassan al-Majid, also known as Chemical Ali.
Majid has already received two death sentences by Iraq's courts.
Some of the alleged crimes were against members of current prime minister Nouri al-Maliki's Dawa party.
The BBC's Caroline Wyatt in Baghdad says Aziz, Majid and more than 20 other defendants are charged with "crimes against humanity" over the alleged persecution of members of the Dawa party, founded in the 1950s.
Nouri al-Maliki, who became Iraq's prime minister in 2006, joined the Dawa party as a young man in 1970.
But he fled Iraq in 1979 and lived as an opposition leader abroad until 2003 and was himself sentenced to death in absentia by Saddam's Baath party government.
The other new charges put forward by the prosecutor in the Baghdad court centre on the arrest of up to 200,000 members of Iraq's political parties - many of whom were sent to jail or executed between 1981 and the 2003 US-led invasion of Iraq.
Majid, considered by many to be Saddam Hussein's right-hand during his years of power, is currently being tried on separate charges over a gas attack that killed some 5,000 Iraqi Kurds in 1988.
Earlier, he was sentenced to death for his role in crushing a Shia uprising in 1991.
And in February, the former defence minister was condemned to hang for genocide over the killing of 100,000 people during the 1988 Anfal campaign against Iraq's Kurds.