Damascus on Monday experienced what some observers are calling the worst day of violence in Syria's capital city since the start of the uprising over 16 months ago.

The violence followed fierce clashes between the Syrian army and rebels in the capital on Sunday, with the Britain-based Syrian Observatory for Human Rights reporting 105 people - 48 civilians, 16 rebels and 41 soldiers - had been killed across Syria.

"The sounds of war are clear throughout the city. They are bouncing off the buildings," Associated Press news agency quoted an activist by the name of Noor Bitar as saying.

All-out 'civil war'

Anti-regime activists say more than 17,000 people have been killed since the beginning of the uprising, and the government says it has lost more than 4,000 security officers. The government has not provided figures on civilian casualties.

The International Red Cross on Monday said that Syria is now in a state of all-out civil war. The formal designation has implications for potential war crimes prosecutions.

As the violence continues, the Syrian regime has grown increasingly isolated. A number of Arab and Western nations have withdrawn their ambassadors in protest over the government's crackdown.

Morocco on Monday asked the Syrian ambassador to leave the country. The AFP news agency reported that within hours, Syria's state-run TV had said its foreign ministry had declared Morocco's ambassador to Syria persona non grata.

International diplomacy has so far failed to put a stop to the violence, with world powers divided over how to resolve the conflict. Many Western nations have called on President Bashar al-Assad to step down from office and have suggested the possibility of a UN-backed military intervention. But Russia, China and Iran prefer non-intervention.

Moscow speaks of 'blackmail'

Russian Foreign Minister Sergey Lavrov on Monday accused the West of using "blackmail" to secure a UN Security Council resolution that could allow the use of force in the country.

"We are being told to either agree to the approval of a resolution that includes Chapter 7 (which provides for possible sanctions), or we refuse to extend the mandate of the observer mission," Lavrov said at a news conference.

"We view this as a completely counterproductive and dangerous approach," he said.

Lavrov also stressed that Western powers should not expect Russia, a long-term ally of Syria, to be able to convince Syrian President Bashar Assad to step down.

"It is simply unrealistic. And it is not a question of our inclinations, our sympathies or our antipathies. He will not leave power. And this is not because we are protecting him, but because there is a very significant part of the Syrian population behind him."

Annan meets Russian leaders

Meanwhile, UN-Arab League special envoy Kofi Annan is on a two-day visit to Russia. He met with Russian leaders in Moscow on Monday and is expected to meet with Russian President Vladimir Putin as a latest effort to broker a Syrian peace plan

Annan has proposed a six-point peace plan that has been constantly flouted since it went into effect in mid-April.

Russia has repeatedly blocked sanctions on Syria at the United Nations and ruled out the use of outside force to end the Syrian conflict. It has also continued to supply the Syrian government with arms since the start of the uprising.

sb/slk (Reuters, AP, AFP)