UNITED NATIONS/MECCA/ALEPPO: The U.N. Security Council Thursday ordered the withdrawal of U.N. observers in Syria as Russia and China stepped up their calls for a cease-fire in the bloody conflict, which activists say has claimed more than 400 lives in the last two days.

The developments came as the Organization of Islamic Cooperation suspended Syria’s membership, citing President Bashar Assad’s violent suppression of the Syrian revolt.

“The conference decides to suspend the Syrian Arab Republic membership in the OIC and all its subsidiary organs, specialized and affiliated institutions,” the group’s closing statement said, following a summit of Muslim leaders in Mecca.

The move had been approved Monday at a preliminary meeting of OIC foreign ministers and was agreed on the summit’s second night despite opposition from Iran.

Syrian Foreign Minster Walid Moallem, in an interview with Syrian state television, said “the Arab League and the OIC are not content to suspend Syria but have hatched a plot against us and must take responsibility for the bloodletting” in his country. In New York, the Security Council decided that the U.N. Supervision Mission in Syria should pull out when its mandate ends at midnight Sunday.

The U.N. originally sent 300 unarmed military observers to Syria in April, but its patrols were suspended in June because of the mounting violence and the force was cut back.

“The conditions to continue UNSMIS were not fulfilled,” France’s U.N. Ambassador Gerard Araud said after a council meeting on the Syria conflict.

“The mission will come to an end at midnight on Sunday,” Edmond Mulet, of the U.N. peacekeeping department, told reporters. He added that the 101 remaining observers and 72 civilian staff would leave Syria by Friday of next week.

The Security Council backed plans by U.N. leader Ban Ki-moon to maintain a political liaison office in Damascus to support the efforts of the successor to U.N.-Arab League envoy Kofi Annan. Ban is still negotiating with former Algerian Foreign Minister Lakhdar Brahimi to take over from Annan.

Russia, which with China has vetoed three U.N. resolutions on Syria, called for international powers to set a deadline for government and opposition forces to halt the conflict and appoint negotiators.

“We believe that those members of the council who insisted that the UNSMIS can’t continue did not really show a commitment to ending hostilities,” Russia’s U.N. envoy Vitaly Churkin told reporters.

He said international powers along with other concerned countries, including Saudi Arabia and Iran, should appeal for a halt to the violence and set the deadline.

Russia has called a meeting in New York Friday of U.N. ambassadors from the so-called Geneva action group on Syria.

Saudi Arabia and Iran would not be at Friday’s meeting because they did not take part in the Geneva meeting on June 30, which included the foreign ministers of Russia, the U.S., Britain, France and China.

It was not immediately clear whether the Western powers, still angry at Russia and China for their veto of the U.N. resolutions, would attend the New York meeting. The U.S. State Department said it had raised questions with Russia about the talks. “Frankly, we’re not sure we understand the objective and the goal of the meeting,” State Department spokeswoman Victoria Nuland told reporters.

Beijing urged a visiting Syrian envoy to implement a cease-fire and accept international mediation to end the violence. “China urges the Syrian government and all concerned parties ... to quickly implement a cease-fire to end the violence and start political dialogue,” Foreign Minister Yang Jiechi told Bouthaina Shaaban.

For his part, France’s foreign minister, speaking during a visit to Jordan, called for a “quick political transition” and said Assad was “butchering his own people and the sooner he goes the better.”

The diplomatic movement came on the heels of a dramatic upsurge in violence, mainly in northern Syria.

The Local Coordination Committees, a network of activists on the ground, said 238 people were killed Thursday, with 123 reported slain in Damascus and in surrounding areas.

The day began with the shelling by Syrian forces of an early morning bread line outside a bakery in Aleppo, which killed at least a dozen people, according to the activists. The LCCs said 193 people were killed Wednesday, with 90 casualties reported in the town of Azaz, close to the Turkish border.

International watchdog Human Rights Watch said more than 40 people were killed and at least 100 wounded in Azaz, many of them women and children. Airstrikes leveled the better part of a poor neighborhood and sent panicked civilians fleeing for cover. The local hospital locked its doors, directing residents to drive their injured to the nearby Turkish border for treatment on the other side.