Iranian leaders on Tuesday declared the end of the territorial hold of the Islamic State militant group (ISIS).
Iranian President Hassan Rouhani made the announcement in a live address on state TV, Reuters reported.
Qasem Soleimami, the notorious and secretive leader of the country's elite Quds Force, sent a message to the country's highest religious figure, Supreme Leader Ayatollah Ali Khamenei, also stating that ISIS's caliphate in Iraq and Syria was finished, according to the Guards official news site Sepah.
The Islamic Republic, a predominantly Shiite nation, has been aiding the government in Baghdad and the regime of Bashar al-Assad in Syria against ISIS and in aid of Assad's six year battle to hold onto power amid a protracted civil war with moderate rebels and Salafists.
It has offered an advisory role to both countries and has provided battlefield assistance in the form of Shiite militiamen from countries such as Afghanistan and Pakistan, as well as the support of its Lebanese proxy group Hezbollah.
But it has not remained immune from the effects of ISIS domestically. In June, ISIS claimed responsibility for twin Tehran attacks on the Iranian parliament and a shrine dedicated to the founder of the Islamic Republic Ayatollah Ruhollah Khomeini. The attacks, carried out by gunmen and suicide bombers, killed 18 people.
Iran retaliated with missile strikes on ISIS-held territory in eastern Syria from a base in western Iran, the first such action against the group to be launched from inside the country.
ISIS no longer fully controls a major town or city after years of U.S.-led coalition and Russian airstrikes. Moscow and Tehran have allowed Syrian regime forces to oust the radical Islamist group from its last strongholds in the eastern Syrian province of Deir Ezzor. The group retains a presence in the eastern Syrian town of Abu Kamal, the central Syrian desert and in the borderlands of western Iraq.
Iran is fighting to maintain and even expand a Shiite crescent of influence across the Middle East, from Beirut to Baghdad, in its rivalry with regional Sunni powerhouse Saudi Arabia. It is supporting Hezbollah in Lebanon, Houthi rebels in Yemen against a Saudi-backed government and the Syrian government.
Its expansion of influence in the Middle East threatens key U.S. ally Israel, which Tehran considers to be its arch-enemy. Its leaders regularly threaten Israel with destruction.
President Donald Trump has railed against Iranian "misbehavior" in the Middle East and has pledged to roll back a landmark nuclear agreement signed with world powers in 2015 that he says is the worst signed in history. He says it returns billions to Iran in frozen assets that it can use to fund its activities in the Middle East.