Kofi Annan, the UN-Arab League special envoy on Syria, said today he would urge President Bashar al-Assad and his foes to stop fighting and seek a political solution to end a year of conflict.
The turmoil has prompted Syria's deputy oil minister to change sides in the first defection by a senior civilian official since the start of a popular uprising against Assad.
In another sign of mounting pressure on Syria, the national currency fell as low as £100 to the dollar from about 47 a year ago. Dealers in Damascus said the pound plunged about 13 per cent in the last 24 hours on fears of US military action.
"As I move to Syria, we will do whatever we can to urge and press for a cessation of hostilities and end to the killing and violence," Annan, due in Damascus on Saturday, said in Cairo.
"But of course, ultimately the solution lies in a political settlement," the former UN secretary-general said before talks with Arab League chief Nabil Elaraby.
"We will be urging the government and a broad spectrum of Syrian opposition to come together to work with us to find a solution that will respect the aspirations of the Syrian people."
China, one of Assad's few friends abroad, said its envoy had given his Syrian hosts a similar message and had prodded them to let relief agencies into strife-hit areas - also the focus of a mission by UN. aid chief Valerie Amos to Syria.
Syria yesterday "welcomed" China's initiative, stressing Beijing's opposition to foreign interference in its affairs.
China is trying to counter Western and Arab charges that it, along with Russia, has colluded in Assad's repression of dissent by twice vetoing UN resolutions criticising him.
The world has failed to stop an unequal struggle pitting mostly Sunni Muslim demonstrators and lightly armed rebels against the armoured might of Assad's 300,000-strong military, secret police and feared Alawite militiamen.
Despite the strains of a conflict in which the security forces have killed well over 7,500 Syrians, according to a UN estimate, and lost at least 2,000 of their own, few senior military officers and government officials have defected.
Deputy Oil Minister Abdo Hussameldin, 58, became the highest-ranking civilian official to do so since the start of an uprising inspired by Arab revolts elsewhere.
"I join the revolution of this dignified people," he said in a YouTube video whose authenticity could not be confirmed.
He said he had been in government for 33 years but did not want to end his career "serving the crimes of this regime", adding: "I have preferred to do what is right although I know that this regime will burn my house and persecute my family."
Burhan Ghalioun, Paris-based leader of the opposition Syrian National Council, welcomed Hussameldin's action, but said the SNC was not in contact with him. "People from the government must continue to join the opposition," he told Reuters.