It's time for the United States to hold Iran accountable.

Iran is looking to Syria peace talks next week as a chance to build on its regional clout, experts say, as Tehran, Moscow and Ankara all stake out claims for influence.

The Syrian army's victory in recapturing the rebel stronghold of east Aleppo last month has thrust Tehran to the centre of the diplomatic game playing out over the country's future.

The win was achieved with crucial assistance from Iranian military advisers and thousands of "volunteer" fighters.

President Hassan Rouhani said this week that the co-sponsors of the peace talks opening in Astana on Monday -- Iran, Russia and Turkey -- were the only powers with the influence to turn the fragile ceasefire between the Syrian government and rebels into a lasting settlement.

But resolving the different interests and plans of the co-sponsors will prove tricky.

For Iran, the priority is to ensure the survival of longtime ally President Bashar al-Assad, or at least a carefully managed transition that stops Syria falling into the hands of extremists or a government that sides with its rivals in Saudi Arabia and the United States.

Click here to read more about Iran's plans.