U.S. Secretary of State Hillary Clinton, during a weekend visit to Riyadh, joined members of the Gulf Cooperation Council in calling for an immediate cease-fire in Syria.
"The world must judge (Syrian President Bashar) Assad by what he does, not by what he says," she said in a statement.
Clinton said during a later visit to Istanbul for a so-called Friends of Syria summit that while Assad pledged to implement a six-point peace plan outlined by joint U.N.-Arab League Envoy Kofi Annan, there was no evidence to support his promise.
"Nearly a week has gone by and we have to conclude that the regime is adding to its long list of broken promises," she said.
Gholam-Reza Karami-Rad, Iran's deputy head of a defense subcommittee, expressed frustration with what he was Western meddling in Syrian affairs.
"Iran, along with the Syrian nation will not allow U.S., Israeli and Saudi plots to be carried out in Syria," he was quoted by Iran's state-funded broadcaster Press TV as saying.
The Syrian conflict topped the agenda during last week's Arab League summit in Baghdad. Iraqi Prime Minister Nouri al-Maliki warned the crisis could evolve into a proxy war between regional adversaries.
The United Nations estimates more than 9,000 people died as a result of internal conflict in Syria. Damascus maintains it is dealing with domestic terrorists backed by foreign agents.