The Vienna talks are a step in the right direction. But to stop the war in Syria we need Syrians at the table – and a date for a UN peace conference. By Martin Griffiths

I have worked for all three UN Envoys to Syria – and I learned one simple lesson: There will be no peace in Syria without Syrians. Syrians have been excluded from decisions about the future of their country for too long. This week’s talks in Vienna are sadly no exception. However, the talks nevertheless offer a diplomatic opportunity to end the war as the Russian intervention could turn into a diplomatic game changer. Russia’s campaign in Syria has succeeded in unexpected ways - and failed in others. As a military venture it has failed with the armed opposition stepping the regime's ground offensive in its tracks. Aleppo is likely to remain divided and haunted by violence. But the Russian gambit has reconfirmed two simple truths: there is no military solution for Syria; and the regime is here to stay.

A political solution needs a timetable

A fortnight ago John Kerry shamed a meeting of diplomats into not leaving the room before they had found some hope for Syria. Resolving differences was beyond the possible but the statement they agreed upon was a step forward. The Vienna talks have put Syria back onto the international agenda. So far so good.

Later this week Secretary Kerry convenes again those same diplomats in Vienna. But this time he will find it much harder to agree on anything. The fate of Assad is the elephant in the room, and it cannot be resolved by words alone. However, the Vienna meeting can be the first step towards a political solution if diplomats in the room remember that diplomacy works best with deadlines and time frames.

What is needed now is a deadline. The United Nations should announce a date for a conclusive negotiation to end the war in Syria‎. However, we need to make sure that this time we will not repeat the mistakes of the past.

The last round of negotiations was a disaster. We did not help the parties’ prepare‎; we did not insist on the armed groups being a part of the negotiation. The women's groups were more for show than for substantive involvement. It was an embarrassment.

This time it needs to be different. Announcing a date certain for conclusive negotiations will allow us to help Syrian parties to get ready. A timetable is pivotal to convince those states who have sponsored parties in the war to use their influence to good effect. Above all, a clear timetable will give Syrians hope that a political solution is possible.

A new peace conference needs to involve Syrians. Let’s bring Syrian people to the diplomatic halls of Geneva. For the first time in the history of peace negotiations let us use a combination of polling and other technology to make the debates genuinely inclusive. Let Syrians run this Syrian-led process. Let Syrians tell us what they think about Assad’s role. Let Syrian can tell us why they have had 'enough' (‘khalas’) of this war and how they imagine the future of Syria.

Calling for a new peace conference carries risks. But failing to give Syrians a chance to negotiate their differences would be unconscionable. Vienna has given peace a chance. Let us turn it into a chance for Syrians.