United Nations Secretary General Ban Ki-moon said Syria's President Bashar Assad must turn his acceptance of a six-point peace plan into action to divert his country from a "dangerous trajectory" with risks for the entire region.
"It essential that President Assad put those commitments into immediate effect. The world is waiting for commitments to be translated into action. The key here is implementation, there is no time to waste," Ban told an Arab League summit in Baghdad on Thursday.
Arab League chief Nabil al-Arabi called Thursday on the Syrian government to "immediately and fully" implement a United Nations-backed peace plan accepted by Damascus earlier this week.
"This plan represents a positive development that can be built on," al-Arabi told the opening session of a pan-Arab summit in the Iraqi capital Baghdad.
"The events recently witnessed by some Arab countries make it necessary for us to listen to the people's voice," he added, referring to a wave of popular revolts that have toppled some autocrats in the region.
At least 10 Arab heads of state and government attended the event, the first pan-Arab gathering to be held in Iraq since May 1990.
The one-day summit was being held in the fortified Green Zone of Baghdad, where large numbers of military and security forces have been deployed to head off potential attacks.
Iraq has been gripped by a surge in terror attacks since U.S .troops completed their withdrawal from the country in December, ending the U.S. presence that dated back to the 2003 invasion which led to the ousting of dictator Saddam Hussein.
Excluded from the summit as a punitive measure, Syria was the main issue on the leaders' agenda.
A final message to be endorsed by Arab leaders was expected to express support for the diplomatic mission of United Nations envoy to the Arab League, Kofi Annan.
The message would also call on the Syrian government and opposition to engage in a "serious national dialogue," according to media reports.
Syria said on Wednesday it would reject proposals from the Baghdad summit after the Arab League suspended its membership in November in protest at Damascus's crackdown on the opposition.
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