International efforts to end Syria’s bloodshed shifted into higher gear yesterday after Kofi Annan, the UN envoy, invited world powers to a ministerial conference on Saturday to endorse a political transition plan.

The “Action Group for Syria” meeting is expected to be attended by several regional states. But Iran – chief ally of President Bashar al-Assad of Syria – was not among those in-vited, despite Russian pressure. Saudi Arabia, which has backed Syria’s opposition, was also not invited.

The decision to hold the meeting came after Moscow signed off on a draft proposal that western diplomats say calls on Mr Assad to step aside and for a national unity government to be formed. That call is expected to be endorsed at the Geneva conference. A statement from Mr Annan’s office said the action group’s objectives were to “identify steps and measures” that would secure full implementation of his peace plan, including a ceasefire and “guidelines and principles” for a transition.