People take part in an Amnesty International demonstration in solidarity with Syria's anti-government protesters, in Berlin August 6, 2011. -Reuters Photo

President Barack Obama spoke separately to France's Nicolas Sarkozy and German Chancellor Angela Merkel as Western nations cranked up pressure on Syrian leader Bashar al-Assad.

“The leaders condemned the Assad regime's continued use of indiscriminate violence against the Syrian people,” a White House statement said Friday.

“They welcomed the August 3 presidential statement by the UN Security Council condemning Syria's actions, but also agreed to consider additional steps to pressure the Assad regime and support the Syrian people.”

The telephone consultations came as Washington appeared to be moving towards a direct call for Assad to leave, after saying this week his presence was now fomenting instability and leading the Middle East down a dangerous path.

The Syrian government has sought to crush the democracy movement with brutal force, killing more than 1,649 civilians and arresting thousands of dissenters, according to the Syrian Observatory for Human Rights Group.

“Seven people were killed in Irbin, two in Damir, and one in Maadamiya, all near Damascus, and five in Homs” during Friday's rallies, Rami Abdel Rahman, head of the Observatory told AFP by telephone.

He said more than 50 people were seriously wounded, while the body of a man with signs of torture was found in front of his home in the Qabun district of the capital after he was allegedly detained by security forces.

State news agency SANA, meanwhile, said two members of the security forces were killed and eight wounded in an ambush on a road in the Idlib region of northwest Syria, near the Turkish border.

And gunmen on an apartment block rooftop in Duma, near Damascus, shot and wounded two other members of the security forces, it said, while assailants also opened fire in Homs.

Communications were completely cut off as the army stepped up an operation to crush dissent in Hama, north of Damascus, where security forces killed at least 30 civilians and wounded dozens more earlier in the week.

“Thousands of demonstrators marched in Deir Ezzor, Daraa and Qamishli in support of the city of Hama despite the extreme heat,” said Abdel Karim Rihawi, who heads the Syrian League for the Defence of Human Rights.

He said they numbered 30,000 in Deir Ezzor alone.

“More than 12,000 people” also marched in Bench, in Idlib province, “to demand the fall of the regime and express their support for Hama and Deir Ezzor,” according to Abdel Rahman.

“Hundreds of people came out of the Al-Mans Uri mosque in Jablah, chanting 'God is with us,'” he told AFP.

The call for Friday's protests came from activists on Facebook group The Syrian Revolution 2011, a driving force behind the demonstrations that have been calling for greater freedoms since mid-March.

The latest crackdown has centred on Hama, where at least 30 people were killed on Wednesday by tanks shelling the city centre.