Former UN Secretary-General Kofi Annan has been appointed as a joint special envoy to Syria for the United Nations and Arab League.
Mr Annan has acted as a diplomatic troubleshooter in several long-running conflicts.
"I am honoured to accept the role and am humbled by the trust and confidence that has been placed in me," he said in a statement issued by the UN European headquarters in Geneva on Thursday.
He said he hoped to ''help bring an end to the violence and human rights abuses, and promote a peaceful solution to the crisis''.
The UN said Mr Annan will be guided by last week's resolution of the General Assembly, which endorsed an Arab League plan for President Bashar al-Assad to step aside.
Mr Annan was UN Secretary-General from 1997 - 2006. After leaving the organisation, he helped negotiate an end to the killing in Kenya after an election there in December 2007.
