President Bashar al-Assad said Sunday that his government faces a foreign plot to destroy Syria, and blamed "monsters" for the Houla massacre, in a rare televised speech delivered in parliament.

Assad's accusations came as Arab leaders called on the United Nations to act to stop bloodshed in Syria and France raised the prospect of military action against Damascus under a UN mandate.

"The masks have fallen and the international role in the Syrian events is now obvious," Assad said in his first address to the assembly since a May 7 parliamentary election, adding the polls were the perfect response "to the criminal killers and those who finance them".

The embattled leader, who was greeted with warm applause from lawmakers, said actrocities like the May 25-26 massacre of at least 108 people near the town of Houla, in central Syria, were committed by "monsters".

"What happened in Houla and elsewhere (in Syria) are brutal massacres which even monsters would not have carried out," he said.

Assad, dressed in a smart suit and tie, also paid tribute to civilian and military "martyrs" of the violence in Syria, saying their blood was not shed in vain.

"We are not facing a political problem but a project to destroy the country," Assad said, adding there will be "no dialogue" with opposition groups which "seek foreign intervention."

"Syria is open to all Syrians regardless of their views, but terrorism can not be part of the political process and we must fight against terrorism to heal the nation," Assad said, dismissing the impact in Syria of uprisings sweeping the Arab world.

On Saturday, violence in Syria killed 89 people, including 57 soldiers, the largest number of casualties the military has suffered in a single day since an uprising began in March 2011, a watchdog said.

The casualties also included 29 civilians and three army defectors killed in various parts of the country in shelling by regime forces or in clashes or gunfire, said the Britain-based Syrian Observatory for Human Rights.

As Arab leaders called for UN action in Syria, France, which spearheaded an air assault against Moamer Kadhafi's forces last year, said it has not excluded military intervention in the country.

France "has not excluded military intervention" in Syria, but only under a United Nations mandate, Defence Minister Jean-Yves Le Drian said on Sunday.

Speaking in Singapore at an Asian security summit, the minister also urged Russia to drop its backing for Assad.

He said that "the Russians have to understand that the future of Syria is not to be considered" with Assad still in power.

"Until then we have to increase pressure, increase sanctions, mobilise public opinion and isolate (Assad) as much as possible -- and make those who still support him lose interest, and I'm thinking of Russia of course," Le Drian said.

On Friday, Russian President Vladimir Putin stood firm against growing pressure over Moscow's position on Syria, opposing foreign military intervention and raising doubts about the effectiveness of sanctions.

Washington and Moscow agreed on the need to work together on Syria, a US official said following a phone conversation between US Secretary of State Hillary Clinton and Russian Foreign Minister Sergei Lavrov.

"Her message to him was: 'We've got to start working together to help the Syrians with Syria's political transition strategy. And I want our people to work together on ideas in Moscow, Europe, in Washington, wherever we need to'."

At a ministerial meeting in the Qatari capital Doha, international peace envoy Kofi Annan warned: "The spectre of an all-out war with a worrying sectarian dimension grows by the day."

"The situation is complex and it takes everyone involved in the conflict to act responsibly if the violence is to stop. But the first responsibility lies in the Syrian government and President Assad," he said.

Earlier, the Arab League's ministerial committee on Syria had called on Annan, who met Assad earlier this week, to set a deadline for the terms of his peace initiative to be met.

"We request Mr Annan to set a time frame for his mission because it is unacceptable that massacres and bloodshed continue while the mission is ongoing indefinitely," Qatari Prime Minister Sheikh Hamad bin Jassim Al-Thani said.

"We demand the UN Security Council refer the six-point (Annan plan) to Chapter VII so that the international community could assume responsibilities," he added.

Chapter VII outlines action the Security Council might take, including military force, in response to threats to international peace, breaches of the peace and acts of aggression.

Tensions from Syria have also spilled across into neighbouring Lebanon, where clashes between pro- and anti-Damascus gunmen left 14 dead and 48 wounded over the weekend in the northern city of Tripoli, security officials said.

The Observatory says as many as 2,300 of the more than 13,400 people killed in Syria since the uprising erupted in March 2011 have died since the so-called ceasefire began on April 12.

Because of the worsening violence and Assad's failure to meet commitments under an agreed peace plan, the United States has warned that it may not agree to renew the UN observer mission when its mandate expires on July 20.