- Kofi Annan's spokesman says the Syrian regime must immediately order a cease-fire
- U.S. official: The armed opposition would could then lay down its arms
- At least 45 people were killed Friday, an opposition activist group says
- Hillary Clinton meets with Saudi Arabia's King Abdullah; U.S. sanctions 3 top Syrian officials
(CNN) -- The Syrian military clashed with defectors in the capital of Damascus on Saturday as regime forces bombarded other towns with heavy gunfire despite the United Nations' call for a cease-fire, opposition activists said.
Gunfire between both sides erupted in the Homs neighborhoods of Baba Amr and Jouret Al-Arayes, the opposition Local Coordination Committees of Syria said. Early-morning shelling also targeted other various areas in Daraa, Idlib, Hama and the Damascus countryside, opposition activists said.
The latest violence comes after a U.N. special envoy ordered President Bashar al-Assad to implement a peace plan and not await concessions from the opposition.
"The government must stop first and then discuss a cessation of hostilities with the other side and with the mediator," Ahmad Fawzi, a spokesman for special envoy Kofi Annan said Friday. "We expect him to implement this plan immediately."
The United States also urged the al-Assad regime to halt the violence first so the armed opposition can lay down its arms.
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Iraqis sending arms, fighters into Syria "Get the guns silenced and then, as Assad takes steps to implement promises he made, then Kofi Annan and others with influence with the opposition would make sure that their guns should be silenced as well," a senior State Department official said.
U.S. Secretary of State Hillary Clinton is in Saudi Arabia for discussions with King Abdullah and leaders of other Gulf states before heading to Turkey for a meeting of the Friends of Syria group Sunday.
At her first stop Friday in Riyadh, Clinton briefed the king and Foreign Minister Saud al-Faisal.
"My understanding is that the conversation on Syria focused on the full range of agenda items that we have for the Friends of Syrian People," a senior State Department official told reporters. Those items include getting humanitarian aid to the Syrians; tightening sanctions and implementing those that already exist; cataloging atrocities; and offering support for the opposition, the official said.
Annan, a former U.N. secretary-general, also plans attend the Friends of the Syria meeting before briefing the U.N. Security Council in a private meeting Monday.
The Syrian National Council, a Syrian opposition coalition, is scheduled to make a presentation at the meeting in Istanbul summarizing its efforts to unite the opposition. U.S. administration officials and others have expressed concern over lack of cohesion and are urging them to lay out a plan for a post al-Assad Syria that would protect ethnic and religious groups.
The fighting cast more doubt on the peace plan brokered by Annan, the United Nations and Arab League joint envoy to Syria. Al-Assad accepted the terms of the plan Tuesday, but violence has persisted. The peace plan calls for an end to the violence by the government and opposition, timely humanitarian aid, the release of arbitrarily detained people, freedom of movement for journalists, respect for peaceful demonstrations and freedom of association.
The United Nations estimates that the Syrian conflict has killed more than 9,000 people since a government crackdown on protesters began in March 2011. Opposition activists put the toll at more than 10,000.
At least 45 people, including four children, were killed across Syria on Friday, said the Local Coordination Committees, a network of activists in Syria.
Syria routinely blames the vaguely defined "armed terrorist groups" for violence in the country, but most reports from inside the nation suggest that the government is slaughtering civilians to quash dissent.
CNN cannot independently confirm reports from inside Syria because the government severely restricts access by international journalists.
CNN's Saad Abedine, Jill Dougherty, Amir Ahmed, Joe Sterling, Tracy Douiery and Gavino Garay contributed to this report.
