Eastern Aleppo has been faced with further destruction last week when Russian aircraft launched a major offensive. Phillip Smyth, an expert on Shiite militias at the Washington Institute for Near East Policy, said that militias are forming a sophisticated ground coalition that is making Iran’s influence even more important. “They are building a force on the ground that, long after the war, will stay there and wield a strong military and ideological influence over Syria for Iran. And there is not much Assad can do to curb the rising influence of these groups, even though Syrian officials are clearly concerned about this, because the militiamen are literally preventing the overthrow of his government.”

Experts say that Iran exerts its power in other countries through the use of Shiite militias. Naylor said: “Iran and its militias have frustrated U.S. officials. While both sides find themselves aligned against the Islamic State in Iraq, they are at cross-purposes in Syria, where anti-Assad rebels receive funding and arms from Washington and its allies.”

He explains that using militias could be beneficial because if the Syrian government can seize Aleppo, the regional balance would be in Iran’s favour which will thwart Saudi plans. Fawaz Gerges, professor of Middle Eastern politics at the London School of Economics, said: “A defeat of the rebels in Aleppo would be a turning point in which Assad captures most of the urban centers of Syria. It would be a setback for Saudi Arabia in its rivalry with Iran, which, as a result, would see its influence in Syria increase even more.”

The situation in parts of Aleppo is worsening – over 200,000 people are faced with a lack of food and medical supplies. Air raids have devastated hospitals, homes and a large part of the city’s infrastructure. 

Zakaria Malahfiji, a member of the Fastaqim rebel force, affiliated with the umbrella Free Syrian Army, said: “They are fighting with passion, and they fight in well-coordinated attacks. I remember one battle where these fighters just kept dying in one spot. One guy would charge, get shot and die, and then another, and then another and then another would do the same thing on the exact same spot. All of them died. They are motivated.”

Abdulmunem Zaineddin, a religious scholar dealing with rebel forces in the battles in Aleppo, said that the Iranian-backed militiamen are extremists that are “spreading Iran’s influence and their extremist ideology, but our revolution is not about religion; it’s about freedom and dignity”.

The militias claim they are involved in the Syrian civil war to defend Shiite shrines and to battle extremist Sunni groups. Hisham Al Mossawi of Harakat al-Nujaba, a militia from Iraq, said: “We don’t want sectarian violence. We want to protect Syria, to protect all that is sacred to everyone from terrorism, from the terrorist groups paid for by Saudi Arabia, Turkey, Qatar and the U.S.”

Naylor said that Hezbollah and Iranian Revolutionary Guards play prominent leadership roles in Aleppo. They direct “the foreign Shiite militiamen, many of whom are recruited by, and trained in, Iran”.

Smyth said: “History proves that whenever Iranians craft groups like these, such as Lebanese Hezbollah, they don’t give up arms, they don’t stand down and they don’t leave territory that they’ve taken. They will be in Syria for years and years, and that will have consequences for everyone.”