Iran's Foreign Minister Mohammad Javad Zarif
Iran's Foreign Minister Mohammad Javad ZarifReuters

Iran on Saturday welcomed the US withdrawal of troops from Syria, saying the US military presence in Syria had been “a mistake, illogical and a source of tension”, Reuters reported.

It was the Islamic Republic’s first comment on US President Donald Trump's decision to pull US forces out of Syria.

“From the start, the entry and presence of American forces in the region has been a mistake, illogical and a source of tension, and a main cause of instability,” Iranian Foreign Ministry spokesman Bahram Qasemi was quoted as saying.

Trump made the announcement on Wednesday, saying US troops succeeded in their mission to defeat the Islamic State (ISIS) jihadist organization and were no longer needed in Syria.

Trump said in a tweet on Thursday that “Russia, Iran, Syria & many others are not happy” about the planned US withdrawal.

Iran is a key supporter of the Assad regime in Syria, having providing the regime with both financial aid and military advisers against a range of opposing forces since the start of the Syrian civil war in 2011.

Near the start of the Syrian civil war, it was reported that then-Iranian President Mahmoud Ahmadinejad had personally sanctioned the dispatch of officers from the Iranian Revolutionary Guards to Syria to fight alongside Assad’s troops.

Ali Akbar Velayati, a top aide to Iranian Supreme Leader Ayatollah Ali Khamenei, made clear last summer that Iran would withdraw its “military advisers” from Syria and Iraq only if their governments wanted it to.

More recently, Iran's defense minister visited Damascus and said his country will continue its support of the Syrian government, while stressing the nature of the two countries' cooperation won't be decided by a "third party."

Tehran opposes the presence of foreign forces in Syria, except for those which have been invited by the Assad government, namely Iranian and Russian forces.