Iraq, which used poison gas during the 1980s, has signed an international treaty that bans the development, production, stockpiling and use of chemical weapons.
U.N. Secretary-General Ban Ki-moon said the move shows Iraq's commitment to disarmament and non-proliferation.
Iraq is the 186th nation to join the pact.
Under then-President Saddam Hussein, Iraq used chemical weapons against the country's ethnic Kurds in 1988, and against Iranian forces during the 1980-88 Iran-Iraq war.
Following the Gulf War of 1991, United Nations inspectors spent years uncovering and destroying an extensive chemical weapons program built up by Saddam Hussein.
In violence today, Iraqi police say a suicide car bomber killed two people and wounded at least two others in the northern city of Mosul. Officials say the attacker detonated his explosives at an Iraqi military checkpoint near the city's center.
The U.S. military has described Mosul as al-Qaida's last urban stronghold in Iraq. Despite the country's sharp decline in violence, ethnically and religiously mixed Mosul remains one of Iraq's most violent cities.
Some information for this report was provided by AFP and AP