New UN envoy Geir Pedersen, who arrived in Damascus Tuesday on his first visit since taking up post, is the fourth head of UN efforts to end Syria's nearly eight-year-old war.
The United Nations has had three previous special envoys to Syria in and all have quit as their peace bids stalled, said an AFP report.
Pedersen -- a seasoned Norwegian diplomat -- took over on January 7 from Staffan de Mistura, who followed veteran Algerian diplomat Lakhdar Brahimi and former UN chief Kofi Annan.
Here is a recap of their efforts in the face of the conflict that killed more than 360,000 people and displaced millions since 2011:
Annan: did his 'best'
The late Kofi Annan, UN secretary general from 1997 to 2006, was on February 23, 2012 named to represent both the UN and the Arab League in efforts aimed at ending "violence and human rights violations, and promoting a peaceful solution to the Syrian crisis".
He visited Damascus several times to meet regime leader Bashar Assad and offered the warring sides a peace plan that was supposed to start with a ceasefire and envisaged a political transition.
But just six months later, on August 2, Annan resigned, saying he had given it his "best" and complaining of a lack of support from major powers, implicitly referring to Russian and Chinese vetoes.
"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," he said.
Brahimi: 'sad' to leave
Lakhdar Brahimi, a former Algerian foreign minister and one of the world's most respected peace envoys, was named to take over on August 17, 2012.
The following month he met Assad in Damascus, warning that the worsening conflict "is a threat to the Syrian people, the region and the world".
He urged "all parties to unite their efforts to find a solution", adding that the Syrian regime needed to assume greater responsibility for a cessation of hostilities.
Brahimi organized in January and February 2014 the first face-to-face negotiations between the regime and the opposition in Geneva, under the leadership of the United States and Russia.
However, he came up against the regime's refusal to discuss the future of Assad and on May 13, after less than two years in the job, he too quit, said AFP.
Brahimi said he was "very sad ... (to) leave Syria behind in such a bad state".
Damascus welcomed the resignation, having accused Brahimi of bias and interference in its internal affairs after he criticized its planned June 2014 presidential election as a blow to peace efforts.
De Mistura: 'sorry'
On July 10, 2014, veteran Italian-Swedish diplomat Staffan de Mistura took on the role, going on to organize nine rounds of indirect negotiations, in Geneva and Vienna, which come to nothing.
In December 2017, de Mistura called the penultimate round of talks a "golden opportunity missed" and accused the regime of not seeking true dialogue with the opposition.
On October 17, 2018, he announced he would step down, citing "purely personal reasons", but with no breakthrough in sight.
He spent his last months in post pushing a UN plan to establish a committee to write a new constitution for Syria, envisaged to provide a basis for ending the war.
But in December 2018 he acknowledged the body would not be in place by year's end, as had been hoped.
"I deeply regret what has not been achieved, and I am sorry more was not possible," he said, noting there were issues with a list of participants proposed by the regime.
An op-ed in Syria's pro-regime Al-Watan newspaper underscored his tense relationship with Assad's regime. "In Damascus, we will never be sorry for Staffan de Mistura's departure," it said according to AFP.
This article has been adapted from its original source.
