The anti-government Free Syrian Army has ordered its fighters to stop offensive operations pending a meeting with Arab League delegates monitoring President Bashar al-Assad's compliance with a peace plan, the rebels' commander said on Friday.

Colonel Riad al-Asaad said his forces had so far been unable to talk to the monitors, in the first week of their month-long mission, and he was still trying to contact them urgently.

I issued an order to stop all operations from the day the committee entered Syria last Friday. All operations against the regime are to be stopped except in a situation of self defence, he told Reuters.

We have tried to communicate with them and we requested a meeting with the team. So far there hasn't been any success. We haven't been given any of the (phone) numbers for the monitors, which we have requested. No one has contacted us either.

How widely Turkey-based al-Asaad's order is heeded by anti-government gunmen inside Syria is in question. A video shot by rebel fighters this week showed the ambush of a convoy of army buses in which, activists said, four soldiers were killed.

Assad has signed up to an Arab League plan for a verifiable withdrawal of his heavy weaponry and army from turbulent Syrian cities where more than 5,000 people have been killed since March, many shot during peaceful anti-government protests but also many killed in rebel attacks and defence actions.

The Arab League mission has met with strong scepticism from the outset, over its makeup, its small numbers, its reliance on Syrian government logistics and an initial assessment by its Sudanese chief that the situation was reassuring.

That comment was met with disbelief in the West on Wednesday but on Friday, Syria's ally Russia accepted the judgement.

Judging by the public statements made by the chief of the mission M. Al-Dabi, who in the first of his visits went to the city of Homs ... the situation seems to be reassuring, the Russian Foreign Ministry said on its website.

Sudan's General Mustafa al-Dabi, who some link to war crimes in Darfur in the 1990s, visited the flashpoint city of Homs briefly on Tuesday and said he saw nothing frightening.

Activist video from Homs over the months has depicted a trail of death and destruction sowed by the military, with hundreds of killings of civilians reported.

The British Observatory for Human Rights, an opposition activist network, said protests broke out on Friday in several areas of the country, including a large gathering of 70,000 in the Damascus suburb of Douma, where monitors were present.

Pro-Assad demonstrations were also reported.

The Observatory said Syrian forces killed four people, including two defectors, in an ambush in Talkalakh near Lebanon's border.

Unfortunately, reports show that the violence has continued in Syria over the past few days, Britain's Minister for the Middle East and North Africa, Alistair Burt, said in a statement.

I urge the Syrian government to meet fully its obligations to the Arab League, including immediately ending the repression and withdrawing security forces from cities. The Syrian government must allow the Arab League mission independent and unrestricted access ... Burt said.

In Brussels, a spokesperson for European Union foreign policy chief Catherine Ashton said the EU also urges Syria to comply with the Action plan of the Arab league in all its components including an immediate end of violence, the release of political prisoners, pulling the military out of cities.

PARTNER FOR PEACE?

The FSA, formed by thousands of defectors from Assad's military and security forces and financed by expatriate Syrians, has gone on the offensive in the past three months, taking the fight to the state rather than simply trying to defend opposition strongholds.

Its decisions are potentially crucial to any peace plan.

Some of (our) soldiers inside Syria are trying to reach out to them but so far it doesn't seem the committee members have been given enough freedom of movement so that the soldiers can meet them. The monitors are escorted by some members of Syrian security. Our defectors if found can be arrested and even executed ... Colonel al-Asaad said.

He said about 1,500 of his men were in custody and out of reach. He wanted to know their fate.

The monitoring teams have encountered a range of problems, from hostility when they turn up under army escort, to random gunfire and communications breakdowns.

Friday could prove another testing days as opponents of Assad take to the streets following Muslim prayers, the main day of protest in the revolts that have swept the Arab world.

In the northern city of Idlib, activists said the army had moved its armour out of sight.

Security forces have moved some of their tanks out of the neighbourhood streets and have put them behind buildings further out, said Manhal of the local coordination committee. They have also moved the tanks out of main streets. Some of them they moved into dugouts.

The Arab League mission has so far failed to end Syria's nine-month orgy of violence in response to demands for Assad to step down, although it was never advertised as a peacekeeping mission as such.

Government security forces shot dead 25 people on Thursday, the Syrian Observatory for Human Rights said. They opened fire on protests in cities around the country, also wounding about 100 people.

Activists contacted by telephone said they had little hope the Arab League monitors would protect them but they still aimed to bring people out into the streets after Friday prayers.

We know that just because they are here, it doesn't mean the bloodshed will stop. But at least they will see it, said one activist in Hama, who was unwilling to give his name.

An Arab League member from a Gulf State played down expectations for the mission.

Even if its report turns out to be negative it would not act as a bridge to foreign intervention but simply indicate that the Syrian government has not implemented the Arab initiative, the delegate told Reuters.

The delegation is not meant to search or inspect anything other than this. It is not a fact-finding mission or an investigative committee ... The commission is meant to tell the League if Syria has committed to withdrawing its military from cities and to check if those who were detained during recent events have been released, and if Arab and international media are able to report on the situation freely or not.

Syria says it is fighting Islamist militants steered from abroad who have killed more than 2,000 of its security forces personnel. Activist sources do not dispute that there has been a significant toll among the security forces.

Most foreign journalists, including Reuters correspondents, are banned from the country, making it impossible to verify the reports on the ground.

(Additional reporting by Thomas Grove in Moscow, Ayman Samir in Cairo, Justyna Pawlak in Brussels and Stephen Addison in London. Writing by Douglas Hamilton; Editing by Giles Elgood)