BEIRUT -- UN observers suspended their patrols in Syria Saturday after recent spikes in violence, the strongest sign yet that an international peace plan was unraveling despite months of diplomatic efforts to prevent the country from plunging into civil war.

The UN observers have been the only working part of a peace plan brokered by international envoy Kofi Annan, which the international community sees as its only hope to stop the bloodshed.

The plan called for the foreign observers to monitor compliance with a cease-fire that took effect on April 12, but they have become the most independent witnesses to the carnage on both sides as government and rebel forces have largely ignored the truce.

Maj. Gen. Robert Mood, the UN mission chief, said intensifying clashes over the past 10 days were "posing significant risks" to the 300 unarmed observers spread out across the country, and impeding their ability to carry out their mandate.

The observers will not leave the country but will remain in place and cease patrols, Mood said in a taped statement, adding the suspension would be reviewed on a daily basis. Teams have been stationed in some of Syria's most dangerous cities, including Homs and Hama.

"The lack of willingness by the parties to seek a peaceful transition, and the push toward advancing military positions is increasing the losses on both sides," Mood said.

The decision came after weeks of escalating attacks, including reports of several mass killings.

The United States reiterated its call for the Assad regime to comply with the plan, "including the full implementation of a cease-fire."

Underscoring the dangers, activists reported at least 50 people killed in violence in several Syrian cities Saturday.

Get the latest news and more great videos at NewsdayTV Credit: Newsday

After 47 years, affordable housing ... Let's Go: Williamsburg winter village ... Get the latest news and more great videos at NewsdayTV

Get the latest news and more great videos at NewsdayTV Credit: Newsday

After 47 years, affordable housing ... Let's Go: Williamsburg winter village ... Get the latest news and more great videos at NewsdayTV

SUBSCRIBE

Unlimited Digital AccessOnly 25¢for 6 months

ACT NOWSALE ENDS SOON | CANCEL ANYTIME