Tehran, December 27 (RHC)-- Iranian President Ebrahim Raeisi says the Israeli regime will definitely pay the price for its criminal act of killing a senior military advisor of the Islamic Revolution Guards Corps (IRGC) in Syria.

In a message on Monday, Raeisi said the vicious act of assassinating the IRGC military advisor in a missile attack in Syria was yet another sign of the usurping Zionist regime's desperation.  

Seyyed Razi Mousavi, who was serving as a military advisor in Syria, was killed in an Israeli airstrike in the Sayyeda Zeinab neighborhood of the Syrian capital of Damascus earlier on Monday.

The president extended his condolences to Mousavi's bereaved family, his fellow comrades in the IRGC and the Iranian nation over his assassination.  He added that the brave military advisor who was one of the companions of Iran's top anti-terror commander Lieutenant General Qassem Soleimani was killed while "safeguarding lofty Islamic values."

General Soleimani, commander of the Quds Force of the IRGC, and his Iraqi trenchmate Abu Mahdi al-Muhandis, the second-in-command of Iraq’s Popular Mobilization Units (PMU), were martyred along with their companions in a US drone strike on January 3, 2020.

Iran maintains an advisory mission in Syria at the request of Damascus with the aim of helping the war-torn Arab country get rid of the foreign-backed militants who have been fighting the democratically-elected Syrian government since 2011.

Earlier in December, Israel killed two IRGC military advisors -- Mohammad Ali Ataee Shoorcheh and Panah Taqizadeh -- in an attack in Syria.

The IRGC announced in a statement that the two officers were martyred against the backdrop of the relentless savagery of the “fake and child-killing” Israeli regime in Gaza.

Iranian Foreign Ministry spokesman Nasser Kan'ani strongly condemned the Israeli regime's terrorist measure to assassinate the IRGC advisor in Damascus.  He said the vicious and cowardly act was another indication of the terrorist nature of the Israeli regime.

"Since its sinister existence, the Zionist regime has committed various kinds of crimes by repeatedly and continuously violating international regulations and norms, and today it has also committed a cowardly and aggressive terrorist act," the spokesperson added.

Kan'ani emphasized that Iran reserves the right to adopt necessary strategies and give a response to the move in due time and place.