Seeking to prevent a bloodbath in Syria's Idlib province, Turkish President Recep Tayyip Erdogan and Russian President Vladimir Putin met for five hours Sept. 17 in Sochi, after which Putin disclosed that a demilitarized buffer zone some 15-20 kilometers (9-12 miles) wide will be activated there, effective Oct. 15.

The decision puts on hold, at least for now, what had appeared to be an imminent attack on Idlib by Russian and Syrian regime forces seeking to conquer the remnants of radical opposition in the seven-year civil war. Such an attack, however, could endanger millions of civilians, along with what Turkey considers moderate rebel groups that have cooperated with Ankara. The Idlib buffer zone aims to separate Syrian regime forces from armed opposition, and moderates from radicals. All opposition groups are to withdraw their heavy arms.

After his meeting with Putin, Erdogan said, “The opposition will remain where they are, but the [radical] groups that we will determine jointly with Russia won't be allowed to operate. The boundaries of the demilitarized zone will be supervised jointly."

The question now is how this comprehensive plan will be implemented in one month. Less than two weeks ago, at a meeting in Tehran, Putin had objected to Erdogan's call for a cease-fire, saying, “Hayat Tahrir al-Sham [HTS] and other radicals aren't at the [negotiating] table. We cannot give guarantees on their behalf.”