PHOTO: Foreign Minister Mohammaad Javad Zarif with Russian counterpart Sergei Lavrov on Tuesday

UPDATE 1645 GMT: Iran has maintained its criticism of the UN Security Council resolution, drafted by Russia and France and passed unanimously, that mandates international monitors in Aleppo and other areas of Syria.

The Secretary of the Supreme National Security Council, Ali Shamkhani, said the resolution tries to ensure the survival of “terrorists” and will not help resolve the humanitarian crisis. He said it may escalate tensions in Syria.

Shamkhani said that, instead of “one-sided resolutions and statements”, the UN Security Council should halt shipment of weapons, fighters, and financial supports to the “terrorists”.

ORIGINAL ENTRY: Even as Iran joined Russia and Turkey in a high-profile meeting on Syria’s crisis on Tuesday, tensions were showing within the Iranian regime over its next steps.

Foreign Minister Mohammad Javad Zarif joined Russia’s Sergei Lavrov and Turkey’s Mevlut Cavusoglu in a joint statement that said the three countries would be “guarantors” of a political resolution and looked to talks between the Assad regime and the opposition in Kazakhstan. Zarif declared, “In the past few days, our cooperation in Aleppo and other besieged areas in Syria led to positive results.”

Referring to the removals of tens of thousands of people from Syria’s largest city Aleppo, the Foreign Minister said, “A large number of civilians have managed to leave the areas under siege,” bring the prospect of re-establishiing “calm and peace”.

After Iran — along with Russia and the Assad regime — had imposed a four-month siege that helped break resistance in eastern Aleppo city, Zarif said th he hoped “efforts can be focused on providing humanitarian aid to the city’s residents”.

But, even as Zarif was meeting Lavrov and Cavusoglu, Iranian officials were challenging Russia over a UN Security Council resolution mandating international monitors for Aleppo.

Ali Shamkhani, the Secretary of the Supreme National Security Council, said the resolution “prioritized the evacuation of militants in Aleppo over the safe exit of civilians”.

After vetoing six Security Council resolutions on Syria since 2011, Russia worked with France to craft a text acceptable to Moscow. The compromise draft was unanimously adopted on Monday.

Pointing to Iran’s “red line” defense of President Assad, Shamkhani said the resolution ignored the role of the Syrian regime.

Iran has propped up Assad since the Syrian uprising began in March 2011, providing billions of dollars in economic assistance and the armed forces to take over operations from the depleted Syrian Arab Army.

Russia has joined Tehran in the essential backing of Assad with its own military intervention, primarily through thousands of airstrikes, since September 2015. However, the two countries have differed at times on the political way forward.

Moscow and Tehran now face the choice of whether to support the Assad regime’s desire to crush the opposition in its remaining areas in Syria, such as Idlib Province in the northwest. Iran has indicated that it will pursue the operations, but Russia has not indicated if — possibly unsettling its new releationship with Turkey, which borders Idlib — it will support the ongoing assault.