Syrian regime planning 'phased' offensive on rebel-held Idlib

The Syrian regime is planning a phased offensive on Idlib, the last rebel stronghold in the country, with its attack targeting the south and west first, an official close to Damascus told Reuters.

Regime forces are planning to target the western town of Jisr al-Shughour and the al-Ghab plain, and the towns of al-Latamenah, Khan Sheikhoun and Maarat al-Numan in the south of the territory, the official said - but not yet Idlib city.

Taking those areas would bring Assad close to regaining control over major link roads running from Aleppo to Hama and Latakia, two of Syria's most important pre-war roads.

"The final touches for the first stage will be completed in the coming hours," the official told Reuters, without saying when it would start.

Meanwhile, regime ally Russia has sent warships to the Mediterranean off the coast of Syria, reports said on Tuesday, supposedly in preparation for the assault. 

Assad has turned his attention to Idlib, the last big rebel enclave that has become home to nearly 3 million people, of whom 1.8 million are displaced after a series of offensives across the country drove rebel fighters and their families to the northwestern province.

It borders Turkey, which fears an offensive may trigger a humanitarian and security catastrophe and a flood of refugees into the country. The UN on Tuesday also warned a large-scale Syrian regime attack "has the potential to create a humanitarian emergency at a scale not yet seen" in the seven-year civil war.

An offensive on Idlib also risks raising tensions with Turkey which has 12 military observation posts inside the province aimed at monitoring a de-escalation zone established under a deal with regime allies Russia and Iran. Media reports have said it has sent concrete blocks over the border to reinforce them in case of an assault.

However Ankara, which supports some rebel groups, is also keen to preserve the three-way alliance and may be prepared to back a more limited offensive against the most extreme opposition factions in Idlib, analysts said.

Russian Foreign Minister Sergei Lavrov on Wednesday said there is "full political understanding" between Russia and Turkey and negotiations were underway to ensure Idlib does not become a breaking point in their alliance.

And Iranian Foreign Minister Mohammad Javad Zarif on Wednesday hailed a "fruitful" meeting with Turkish President Recep Tayyip Erdogan, following previously unannounced talks in Ankara.

Erdogan and his counterparts Hassan Rouhani of Iran and Russia's Vladimir Putin are due to meet in Iran for a third summit on Syria on 7 September, Turkish reports have said.

Agencies contributed to this report.