President of the Iraqi Kurdistan Region, Massoud Barzani called Monday for cooperation between Kurdish and Arab forces in the fight against Islamic State (IS), in a meeting with Arab tribal leaders in Rabia and Zammar. Barzani said the doors were open for Arabs to fight alongside the Kurdish Peshmerga fighters against IS militants in the Iraqi city of Nineveh. He expressed full support to the formation of joint battalions with the Arab tribes to fight IS, explaining that no one will pay for a crime committed by others, in reference to the help provided by some locals to IS militants. Barzani stressed that Kurdish fighters won't allow any assault on a member of the Arab tribes, adding that everyone has freedom to choose their religion and political beliefs, referring to the shocking crimes committed by IS against Yazidis. The Kurdistan regional government in Iraq said Saturday it has obtained evidence of the IS' use of chlorine gas as a chemical weapon against Kurdish fighters. The government revealed that Kurdish fighters took soil and clothing samples from an IS' suicide bombing attack in northern Iraq, January 2015, proving the use of chlorine as a chemical weapon.