The Syrian regime threatened to use its chemical and biological weapons in case of a foreign attack.
Netanyahu said a chaotic "regime collapse" would leave Syria's weapons sites unguarded than a regime change.
Russia, a longtime Syria ally, is facing intense criticism that it is standing in the way of an end to the conflict there.
The statement came as UN observers gathered new details on what happened in a village where dozens were reported killed.
Annan gave a bleak assessment of the situation in Syria 15 months on from the start of the anti-Assad uprising.
Western and Arab states opposed to Syrian President Bashar al-Assad put the blame for the deaths squarely on the government.
The head of Formula One's governing body was unrepentant about the decision to race in Bahrain.
The discovery of a protester's body overshadowed the return of the Formula One Grand Prix to Bahrain.
Syria also said it would keep its forces in cities to "maintain security" until it is safe to withdraw in line with the peace deal.
The blast came two days before an Arab League committee was due to discuss an initial report by Arab observers.
The opposition wants the strike to remain in force until the regime pulls the army out of cities.
Nine months after the popular uprising that pushed Mubarak out, protesters are back in the streets.
Two days of voting begin on Monday in the first stage of a complex, drawn-out election that will be completed in January.
Nine students hit by pepper spray were treated at the scene, two were taken to hospitals and later released.
California University ordered probe after a video showing an officer spraying pepper spray on student protesters went viral.
Rasanath Das, 32, is an ex-investment banker turned Hindu monk and an alumnus of IIT Bombay.
Evicted protesters will march to show their battle against economic inequality.
For the past two months, Zuccotti Park in Manhattan has hosted a round-the-clock demonstrations.
The warning came hours after UN chief Ban Ki-moon asked Syria to 'immediately' end attacks on civilians.
Activists said Syrian forces killed more than 50 civilians in the last 48 hours.