The Syrian regime has declared 17 foreign diplomats to be persona non grata, effectively banning them from Damascus.
They include British, Turkish, US and Canadian diplomats along with many more from EU countries.
Many of those nations had co-ordinated the expulsion of Syrian envoys last week after the massacre in Houla that killed 108 people, nearly half of them children.
Almost all of the countries banned had already recalled their diplomats anyway.
Syria’s Deputy Foreign Minister Faisal Maqdad said: “We regret that we had to take this measure, because those countries do not want this (Annan) peace plan to succeed. They do not want the stability that all Syrian people want to return to Syria.”
Turkey has been welcoming thousands more refugees escaping the violence at home. They fled as Syrian government helicopter gunships bombarded rebels in Latakia province.
The latest events have led Saudi Arabia’s foreign minister to say the Gulf states have begun to lose hope in the peace plan, brokered by the international mediator Kofi Annan.