Syrian President Bashar al-Assad has welcomed Russian Defence Minister Sergei Shoigu to capital Damascus as Syrian forces supported by the Russian army prepare to make a final push into parts of the eastern city of Deir Az Zor.



Shoigu gave a letter from Russian President Vladimir Putin to Assad "congratulating him on lifting the siege” imposed by the Islamic State of Iraq and the Levant (ISIL, also known as ISIS) in the city of Deir Az Zor, according to a statement by the Syrian presidency.



Last week Syrian troops, backed by Russian air attack, broke the siege of two enclaves in and around Deir Az Zor, which had been encircled by ISIL fighters for nearly three years.



An unwavering ally of Assad's regime, Russia militarily intervened in the Syria's six-year conflict in September 2015 when the government was in trouble in its fight against rebels and armed groups.



The Damascus government has had many victories since and now controls nearly all Syria's main cities.

Blow to ISIL

The loss of Deir Az Zor would be a major blow to ISIL, whose territory in Syria and neighbouring Iraq has been shrinking.

Shoigu and Assad, who last met in June 2016 in Damascus, discussed their "military and tactical cooperation... for the destruction of the Islamic State group in Syria," a statement from the Russian defence ministry said.

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According to the Syrian president, the meeting emphasised "the importance of the Astana process," with a new round of peace talks scheduled on Thursday and Friday aiming to strengthen deescalation zones meant to allow the establishment of a lasting ceasefire in Syria.



In a statement issued Tuesday, the Russian army claimed that more than 450 ISIL fighters had been killed in the Deir Az Zor offensive.



"Only yesterday, the Russian air force carried out more than 50 flights to help the Syrian army's offensive," the statement said.