Story highlights Iran has been invited to Syria peace talks in Vienna this week, Russia says

Iran also says it's losing more of its key military leaders in Syria

One U.S. analyst says Iran is "frankly guiding the entire Syrian front"

(CNN) Iran is increasing its military presence in Syria, a top commander told Iranian television Monday.

Brig. Gen. Hossein Salami, deputy commander of the Islamic Revolutionary Guards Corps, said Iran is increasing the quality and quantity of its presence in Syria, according to Iranian media. He described their mission as an advisory role to help the Syrian army loyal to President Bashar al-Assad.

He said the Iranian officers were providing tactical help for Syrian commanders of battalions in direct battles, as well as weapons and ordnance, operational assistance and help with strategic planning, according to a Tasnim report.

He also conceded that the number of Iranian casualties in Syria had increased.

Earlier this month, Iran announced that a high-ranking general, Hossein Hamedani of the Revolutionary Guards, was killed by Islamic State fighters near Aleppo. More recently, two other Guard commanders and a former bodyguard to former Iranian President Mahmoud Ahmadinejad were killed, according to the semiofficial Fars news agency.

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