Meanwhile, the opposition-rebel High Negotiations Committee suspended formal participation in the Geneva talks, which had resumed last Wednesday, although it is remaining for informal discussions. The opposition-rebel coordinator, Riad Hijab, said that it was unacceptable for talks to continue if the regime and its foreign allies maintained sieges and bombing of civilian areas. A letter by rebel factions called on the bloc to “take firm and decisive stances towards the half-solutions being propagated…by the regime’s allies…and [UN envoy Staffan] de Mistura”.

President Assad and the regime delegation have said that they will not discuss a transitional governing authority, the centerpiece of international proposals since June 2012. The regime has also maintained sieges on several areas on Syria, refusing access to aid agencies despite a UN Security Council resolution and the terms of a February 27 cessation of hostilities.Mohammad Alloush, a senior negotiator for the HNC, said:We want real negotiations, not farcical ones.

When there are 70 airstrikes, and when there is mobilizing of troops, when Iran sends further armed men and Russia sends a large group of rockets and unmanned planes, all this tells us that there is no real will for a political solution that ensures the safety and stability in the country.

UN envoy de Mistura responded: It is one way for them to display their displeasure and concern for what they perceive to be a substantial deterioration of the humanitarian situation and a deterioration of the security environment, particularly in Aleppo.They told us however their intention to remain in Geneva, in their hotel, and possibly at my own suggestion, to pursue technical discussions with myself and my team.