DAMASCUS, June 11: UN-Arab League envoy Kofi Annan said he was gravely concerned by increased fighting between Syria’s troops and rebel forces as violence on Monday killed dozens of people across the country.

Annan “is gravely concerned by the latest reports of violence coming out of Syria and the escalation of fighting by both government and opposition forces,” his spokesman Ahmad Fawzi said.

Fawzi said Annan, who brokered a faltering plan aimed at ending 15 months of bloodshed in Syria, cited shelling in Homs and the reported use of mortars, helicopters and tanks in Al-Heffa, a beleaguered town in the northwest.

“There are indications that a large number of civilians are trapped in these towns,” said Fawzi.

“The Joint Special Envoy demands that the parties take all steps to ensure that civilians are not harmed, and further demands that entry of the UN Military Observers be allowed to the town of Al-Heffa immediately.”

On the ground, helicopter gunships fired on rebel positions in Al-Heffa as well as the opposition stronghold of Rastan, in Syria's central Homs province.

An activist broke down in tears as she told this correspondent via Skype that army tanks were sitting on the edge of Al-Heffa, a town of 30,000 people set in rugged countryside near the Turkish border.

“They have never come this close before,” Sem Nassar said, adding “There's only one doctor working to treat the wounded in the town,” and that most of the residents had fled.

The Syrian Observatory for Human Rights said nationwide violence cost the lives of at least 52 on Monday, adding to its overall toll of more than 14,100 people killed since an anti-regime revolt erupted in March 2011.

The bloodshed has persisted despite the presence of 300 UN observers charged with monitoring a putative truce launched April 12.

With Annan's peace plan faltering, world powers are divided on how to stop the crisis. The West has called for tougher sanctions and for President Bashar al-Assad's departure, while Russia and China reject any foreign interference.

Russian Foreign Minister Sergei Lavrov will visit Iran on Wednesday to discuss upcoming talks in Moscow on the Syria crisis, as well as Tehran's nuclear programme, his office said.

Moscow has proposed holding an international conference on Syria aimed at saving Annan's tattered plan and has pressed for Iran's inclusion despite strong reservations from Britain, France and the United States.

“Without Iran's involvement, the opportunity to exert constructive pressure on Syria will not be implemented in full,” its foreign ministry said.

France said it would hold talks with Russia on its idea of an international Syria conference, as it urged the new head of the Syrian National Council to unite the opposition.

Paris has said it backs Annan's bid to bring key powers into a contact group on the Syria crisis, but Foreign Minister Laurent Fabius has said Iran could in no way be involved in such a group.

It also congratulated Kurdish activist Abdel Basset Sayda on his naming as the SNC's new leader at the weekend, calling on him to work to bring the diverse regime opponents together.

Paris is scheduled host the next meeting of the pro-opposition “Friends of Syria” group on July 6, in which Russia, China and Iran have never participated.

The new head of Syria's main opposition group called on Sunday for mass defections from a regime he says is “on its last legs”.

“We are entering a sensitive phase. The regime is on its last legs,” Sayda, a Kurdish activist, said shortly after being named the new leader of the SNC.

“The multiplying massacres and shellings show that it is struggling,” he said of mass civilian deaths, the latest of which saw 20 people, mostly women and children, killed in a bombardment of the southern city of Daraa on Saturday.

At his first news conference since taking over the reins, Sayda called on all members of the Damascus regime to defect, while reaching out to minority groups by promising them a full say in a future, democratic Syria.

“The Annan plan still exists but it has not been implemented,” Sayda said.

The rebel Free Syrian Army, meanwhile, has called for a campaign of civil disobedience and urged officers and troops in Assad's military to jump ship and join the opposition ranks.

Colonel Kassem Saadeddine, spokesman for the opposition fighters in Syria, urged officers and men in Syria's regular army “whose hands are not tainted with blood to join the fighters”.—AFP