"Syria renders all possible assistance to keep the security, stability and unity of Iraq," Former Iraqi Interior Minister Falah al-Nakeeb said.
He noted that the responsibility of security on the Iraqi side of the border lies with the Iraqi authority.
"It is not fair to hold Syria responsible for both," he concluded.
The United States has accused Damascus of not doing enough to stop anti-US Arab militants from crossing into neighboring Iraq to destabilizing situation there.
But Syria insists it has done its best to control the border.