Syrian President Bashar al-Assad has expressed gratitude to the Leader of Islamic Revolution Ayatollah Seyyed Ali Khamenei and the Iranian nation for supporting his country in the fight against terrorism, hailing Iran's role in the Syrian Army's recent success in breaking the siege of Deir al-Zor. In a letter to Ayatollah Khamenei, dated Sept. 6, the Syrian president dedicated the victory in Deir al-Zor to the Leader and the Iranian government and nation, Tasnim News Agency reported. Assad said the "strategic achievement" of breaking a three-year siege imposed by the self-styled Islamic State terrorist group on Deir al-Zor was gained with the help of Syria's allies and friends. He said Syria believes Iran, which has always contributed to the anti-terror campaign, has a share in the recent victory, and praised the Islamic Republic for its "principled policies" in the war on terrorism and in supporting the Syrian people. Assad pledged that the Damascus government, together with Iran, will continue combating "tyranny and aggression" to overcome the threat of terrorism.