The 21 UN peacekeepers taken hostages in the Golan are expected to be freed on Saturday after the Syrian regime agreed to observe a ceasefire in deal with the United Nations, a watchdog said.

In New York the United Nations said efforts to secure the Filipinos would resume on Saturday after they were halted on Friday amid intense shelling of the area by regime forces.

"An agreement has been reached between the Syrian regime and the United Nations to stop the bombing between 4pm (0800 GMT) and 6pm (1000 GMT) on Saturday, in order to allow the evacuation of the 21 peacekeepers," Syrian Observatory for Human Rights director Rami Abdel Rahman told AFP.

"A Red Cross delegation should accompany the UN team to the area to evacuate the peacekeepers."

The Observatory is in contact with the Yarmuk Martyrs battalion, the Syrian rebel group that on Wednesday captured the peacekeepers.

Earlier UN peacekeeping spokeswoman Josephine Guerrero said efforts to secure their release will resume Saturday.

"Arrangements were made with all parties for the release of the 21 peacekeepers," she said

"But due to the late hour and the darkness it was considered unsafe to continue the operation. Efforts will continue tomorrow."

UN peacekeeping chief Herve Ladsous said Jamla village where the soldiers are being held came under "intense shelling" on Friday.

That was denied by Syrian UN Ambassador Bashar Jaafari, who said Syrian forces were doing "everything in order to bring back safely the peacekeepers."

Abdel Rahman said a UN convoy entered Jamla to collect the peacekeepers on Friday but the army shelled the area.

"When the UN vehicles entered into Jamla, the Syrian army shelled a nearby village. The UN cars then withdrew from Jamla," he said.

Ladsous expressed hope that a possible ceasefire would lead to the freeing of the peacekeepers, who have been held by Syrian rebels since Wednesday.

"There is perhaps a hope, but it is not done yet... that a ceasefire of a few hours can intervene which would allow for our people to be released," adding that they were held in different locations within the village.

US State Department spokeswoman Victoria Nuland accused the Syrian regime of "making it impossible for UN negotiators to get in there and try to resolve it."

The Filipinos, members of the UN Disengagement Observer Force (UNDOF) monitoring the armistice line between Syria and Israel that followed the 1973 Arab-Israeli war, were abducted just a mile to the Syrian side of the line.

The rebels are demanding that Syrian troops move 20 kilometres (12 miles) back from Jamla, an area at the southern end of the armistice zone in the Golan, Philippine foreign affairs spokesman Raul Hernandez said.

"We are trying to intensify our negotiations with the rebel groups," he said adding that the hostages were nonetheless being treated well.

The Observatory said the rebels had added a fresh demand.

"They are now demanding a new condition -- that the International Committee of the Red Cross guarantees the safe exit from the strife-torn area of Jamla of civilians," Abdel Rahman said.

In Manila, Xy-son Meneses, whose brother Captain Xy-rus Meneses is among the peacekeepers held in Syria, issued a televised appeal for the peacekeepers' release.

"They are not there to cause trouble but to help maintain peace in Syria so I ask if they can release them," he said.

Concern has been mounting that the abduction might prompt more governments to withdraw troops from the already depleted UN mission.

Israeli officials warned that any further reduction in its strength risked creating a security vacuum in the no-man's land between the two sides on the strategic Golan Heights, which it seized in the 1967 Six-Day War.

The Israeli army revealed that it helped eight other UN peacekeepers re-deploy through Israeli-held territory overnight from an isolated post in the area where the hostages are being held.

An army spokeswoman said Israeli troops escorted them north to another UN base.

World powers remain at loggerheads over the way forward, with Western governments firm in their demand for President Bashar al-Assad to quit, and China and Russia equally firm in their opposition to any imposed regime change.

"You know that we are not in the regime-change game," Russian Foreign Minister Sergei Lavrov reiterated on Friday. "We are against interference in domestic conflicts," he told the BBC.

On Friday the Syrian army pounded rebel areas in the central city of Homs with warplanes and tanks, the Observatory said, as protesters demonstrated against the army offensive.

A total of 121 people were killed in the Syrian conflict on Friday, the Observatory said.