Former U.N. chief Kofi Annan says he expects the Syrian government to respond on Tuesday to his proposals to resolve the country's deadly violence from an on-going crackdown on dissent.

“I am expecting to hear from the Syrian authorities today since I have left some concrete proposals for them to consider. Once I receive their answer we will know how to react. But let me say the killing and violence must cease.”

Annan, now the U.N.-Arab League special envoy for Syria, commented in Turkey after meeting with members of the Syrian National Council, the main opposition grouping outside Syria. Annan left Damascus on Sunday, after two days of talks ended without a settlement.

Meanwhile, Syrian news reports say President Bashar al-Assad has set May 7 as the date for parliamentary elections. The elections are part of what the government calls a series of reforms based on a new constitution approved by referendum in February.

Opposition groups say the constitution is illegitimate and are demanding Mr. Assad must leave power.

Also Tuesday, Arab League chief Nabil Elaraby called for an international probe into civilian deaths in Syria, saying they amounted to “crimes against humanity.”

He cited reports of deadly violence in areas including the northern Idlib province and the flashpoint city of Homs. On Monday, Syrian activists said soldiers and pro-government forces killed dozens of men, women and children in the city, a former rebel stronghold. The government disputes the blame and says “terrorists” are responsible for the killings.

The Syrian Observatory for Human Rights says deadly clashes erupted in several regions on Tuesday. The British-based opposition group says rebels killed at least 21 members of forces loyal to President Assad during ambushes in Idlib province and the southern Deraa region.

The United States, Britain and Russia have each called for a halt to the violence in Syria, but the United Nations Security Council remains divided on how to resolve the crisis.

Russian Foreign Minister Sergei Lavrov says his country will press Syria to accept a plan that calls for a “simultaneous” truce between government forces and armed rebels.

He commented Tuesday, a day after Security Council foreign ministers met in New York.

Russia and China have vetoed Security Council resolutions condemning the Syrian government's deadly crackdown on its opponents. They say the resolutions called for interfering in Syria's internal affairs.

British Foreign Secretary William Hague said the Security Council has “failed” in its responsibilities to the Syrian people and that the diplomatic challenge now is to build on areas where the international community agrees.

“It is encouraging that everybody is talking about a political process. Everybody is now talking about humanitarian aid being delivered, about a cessation of violence and everybody on the United Nations Security Council of course is supporting the work of Kofi Annan. So there are now many common elements, but the task of bringing them together in a resolution remains.”

U.N. officials estimate that 7,500 people have died in the year-long violence.