Kofi Annan, the U.N.-Arab League joint envoy for Syria, will step down from his post at the end of the month, dealing a decisive blow to international efforts to find a diplomatic solution to a political crisis that has already left more than 10,000 people dead and pitched the country into deepening civil war.
The announcement was made by Ban Ki-moon, the U.N. secretary-general, who said that he had accepted Annan's request and that he would mount a search for a replacement. "It is with deep regret that I have to announce the resignation of the U.N.-League of Arab States joint special envoy for Syria, Mr. Kofi Annan," Ban said.
The announcement comes nearly two weeks after Russia and China blocked a Western-backed resolution that would have reinforced Annan's mediation effort with the threat of sanctions. It was their third Security Council veto since last fall.
The impasse in the Security Council effectively undermined Annan's negotiating leverage and set the stage for the Syrian forces to enter a new, more violent phase of civil war, according to council diplomats.
In a press conference in Geneva, Annan said that he had taken on to the so-called "mission impossible" in Syria because he believed he had a "sacred duty to do whatever was in my power to help the Syrian people find a peaceful solution to this bloody conflict."
But the "increasing militarization on the ground and the clear lack of unity in the Security Council have fundamentally changed the circumstances for the effective exercise of my role," Annan said. "Without serious, purposeful, and united international pressure, including from the powers of the region, it is impossible for me or anyone to compel the Syrian government in the first place, and also the opposition, to take the steps necessary to begin a political process."
In the past two weeks, the United States and its Western partners have been looking for ways to increase their support for the armed opposition, but they have stopped short of committing lethal support to the anti-Assad movement, fearing it could potentially benefit foreign extremists, including al Qaeda, seeking inroads in Syria.
In making the announcement, the U.N. chief faulted both the Syrian government and the armed opposition for refusing to embrace Annan's six-point peace plan, and accused the U.N. Security Council of failing to provide Annan with the political backing he needed to succeed.
"Tragically, the spiral of violence in Syria is continuing," Ban said in a statement released from U.N. headquarters this morning. "The hand extended to turn away from violence in favour of dialogue and diplomacy -- as spelled out in the Six-Point Plan -- has not been not taken, even though it still remains the best hope for the people of Syria."
Ban said "the [Syrian] Government and the opposition forces continue to demonstrate their determination to rely on ever-increasing violence. In addition, the persistent divisions within the Security Council have themselves become an obstacle to diplomacy, making the work of any mediator vastly more difficult."
It remained unclear who would be willing to replace Annan. The United Nations had previously considered asking former Finnish President Martti Ahtisaari to take on the job.
Ban said that he was "indebted" to Annan for taking on such an intractable diplomatic challenge. "Kofi Annan deserves our profound admiration for the selfless way in which he has put his formidable skills and prestige to this most difficult and potentially thankless of assignments."
He said the United Nations, which continues to oversee a U.N. monitoring mission in Syria, is committed to pursuing a diplomatic outcome in Syria. "This can only succeed -- indeed any peacemaking effort can only prosper -- when the parties to the violence make a firm commitment to dialogue, and when the international community is strongly united in support," he said.
But Annan said that peace won't come if the warring parties don't want it.
"You have to understand, as an envoy, I can't want peace more than the protagonists, more than the Security Council or the international community for that matter."
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Longtime Washington Post correspondent Colum Lynch reports on all things United Nations for Turtle Bay.