Iranian Deputy Foreign Minister, Hossein Amir Abdullahian, expressed Tehran's deep concern over the use of chemical weapons by terrorists in Syria, warning the US, Britain, France and some regional countries that are supporting the extremists of the repercussions of this act on the region's security. "Iran, the biggest victim of chemical weapons-related issues, strongly denounces the use of these weapons by the extremist terrorist groups operating in Syria under the name of opposition," said Abdullahian in a statement on Saturday. He expressed deep regret over the use of chemical weapons against the people and army of Syria. The Iranian official stressed the responsibility of the governments of the US, Britain, France and some regional countries for arming the extremist groups in Syria, warning them of the consequences of this act on the security of the region.