Iraq executed 23 people during two days in September, most of them convicted on terrorism charges, the justice ministry said Tuesday.

Twenty of the 23 were either Al-Qaeda members or otherwise involved in terrorism, while three were convicted of unspecified "criminal charges," a ministry spokesman said.

The executions were carried out on September 22 and 26.

They take to at least 90 the number of people who have been put to death in Iraq this year, according to an AFP tally based on reports from the ministry and officials.

Executions in Iraq, which are usually carried out by hanging, have drawn widespread condemnation from the European Union, the United Nations and rights watchdogs.

"The Iraqi authorities have chosen to defy repeated calls not to execute prisoners and to rely on tainted 'confessions' obtained under torture," Hassiba Hadj Sahraoui of Amnesty International said last month.

"That a death sentence could be imposed after obviously grossly unfair trials beggars belief."

UN human rights chief Navi Pillay said this year that Iraq's criminal justice system was "not functioning adequately."

She highlighted "numerous convictions based on confessions obtained under torture and ill-treatment, a weak judiciary and trial proceedings that fall short of international standards."

"The application of the death penalty in these circumstances is unconscionable, as any miscarriage of justice as a result of capital punishment cannot be undone," Pillay said.