Jordan's King Abdullah has become the first Arab ruler to call for Syrian president Bashar Assad to step down.
The statement came as Arabs closed ranks against Damascus with the Arab League voting to suspend Syria over attacks on protesters that the UN estimates have killed 3,500 people since mid-March.
"If Bashar (Assad) has the interest of his country, he would step down, but he would also create an ability to reach out and start a new phase of Syrian political life," King Abdullah told the BBC in an interview.
Earlier Syrian Foreign Minister Walid al-Moallem accused Arab nations of conspiring against Damascus, calling Saturday's near-unanimous vote at the Arab League's headquarters in Cairo "shameful and malicious."
The vote was a stinging rebuke to a regime that prides itself as a bastion of Arab nationalism and left Syria increasingly isolated over its crackdown.
"We wanted the role of the Arab League to be a supporting role, but if the Arabs wanted to be conspirators, this is their business," al-Moallem said at a news conference in Damascus, betraying his country's deep alarm over the decision.
The vote to suspend Syria - a major boost for the Syrian opposition - put Damascus in direct confrontation with other Arab powers, including Qatar and Saudi Arabia, who were pushing for the suspension.
The unified Arab position also puts more pressure on the UN Security Council to impose sanctions, despite objections by Syrian allies Russia and China. Of the Arab League's 22 members, only Syria, Lebanon and Yemen voted against the suspension of Syria, with Iraq abstaining.
In Brussels EU foreign ministers decided to impose additional sanctions on 18 Syrians and organisations in response to the killings of protesters.
The names of those sanctioned will not be known until they are published in the EU's official journal in a day or two. Sanctions generally include visa and travel bans on people, the freezing of assets, and prohibitions on trade.