Russia resumed air strikes against insurgents in Idlib on Tuesday following weeks of bombardment and shelling by pro-Syrian government forces in an apparent prelude to a full-scale offensive against the rebels’ last major enclave.

The leaders of Russia, Turkey and Iran are due to meet on Friday in Iran and are expected to discuss the situation in northwestern Syria. Turkey, which backs rebels against Assad, has said an offensive on Idlib would be disastrous.

“We will take the situation to a positive point at this summit. … God willing, we will be able to prevent the Syrian government’s extremism in the region,” the Hurriyet newspaper quoted Erdogan as saying.

On Wednesday, Turkey’s defense ministry said Turkish and Russian officials had met in Ankara to hold five days of meetings on developments in Syria. It said joint efforts would continue.

Russia’s ambassador to Turkey was later cited by NTV as saying Turkey and Russia were in contact regarding the latest developments in northern Syria.

“The summit that will be held in Iran on Friday is a great opportunity for a solution in Syria,” Ambassador Aleksei Erkhov was quoted as saying.

Reporter’s code: 50101