An Australian move to expel two Syrian diplomats has been followed by Western nations around the world in an effort to pile pressure on president Bashar al-Assad.

Foreign Affairs Minister Bob Carr announced late on Tuesday afternoon that Syrian chargé d'affaires Jawdat Ali and another diplomat would have 72 hours to leave the country.

Senator Carr said Australia took the action "with other nations around the world" and in the hours that followed, the United States, Britain, France, Italy, Canada, Germany, Spain and other countries all made similar announcements.

The coordinated move comes in the wake of a gruesome massacre in the Syrian town of Houla which led to the deaths of more than 100 people at the weekend, including dozens of children.

Senator Carr says he hopes the Syrian regime will get the message that the world has run out of patience.

"This is the most effective way we've got of sending a message of revulsion to the Syrian government," he said.

Space to play or pause, M to mute, left and right arrows to seek, up and down arrows for volume. Listen Duration: 4 minutes 15 seconds 4 m 15 s Naomi Woodley reports on the expulsion Download 2 MB

Senator Carr says Australians are appalled by the Houla massacre.

"They're appalled at a regime that could connive in or organise the execution, the killing of men, women and children," he said.

"Australians want that conveyed. And the best way of conveying it right now, given the restraints of what we deal with in the UN in New York, is to expel Syrian diplomats from Australia."

Senator Carr also set out what the Government and the international community expects before the diplomats can be re-accepted.

This includes an end to military activity - particularly in built-up areas, the withdrawal of artillery and tanks from built-up areas, and negotiation between the Assad regime and their political opponents.

In recent days, the Syrian regime has not indicated it is willing to do any of those things.

Space to play or pause, M to mute, left and right arrows to seek, up and down arrows for volume. Watch Duration: 4 minutes 18 seconds 4 m 18 s Bob Carr speaks to 7.30

'Bold steps'

Meanwhile, UN special envoy and international mediator Kofi Annan has met with Mr Assad in an effort to reinforce a ceasefire that was agreed to in April.

Mr Annan told Mr Assad that "bold steps" were required for his six-point peace plan to succeed, including a halt to violence and release of people arrested in the uprising, a statement said.

"Joint special envoy Kofi Annan met president Bashar al-Assad this morning to convey the grave concern of the international community about the violence in Syria, including in particular the recent events in Houla," said the statement issued by his spokesman Ahmad Fawzi after talks in Damascus.

"He conveyed in frank terms his view to president Assad that the six-point plan cannot succeed without bold steps to stop the violence and release detainees, and stressed the importance of full implementation of the plan."

About the same time as the meeting was being held, the UN human rights office confirmed that most of the 108 people killed in Houla at the weekend were executed civilians.

Fewer than 20 of those killed died from artillery and tank fire, it said. And most of them were innocent families, shot in their own homes.

Witnesses and survivors have told UN investigators that most victims died in two bouts of summary executions carried out by pro-government "shabbiha" militiamen, UN rights spokesman Rupert Colville said.

"It is believed at this point, and I would stress we are at very preliminary stages, that under 20 of the 108 can be attributed to artillery and tank fire," he added.

"What is very clear is that this was an absolutely abominable event that took place in Houla, and at least a substantial part of it were summary executions of civilians - women and children," he said.

"At this point it looks like entire families were shot in their houses," he said.

Some 49 children and 34 women were among the known victims, but the toll was not definitive, Mr Colville said, adding: "There are reports of more deaths."

"Almost half of the ones we know of so far are children - that is totally unpardonable - and a very large number of women as well."

Kofi Annan meets Bashar al-Assad for crunch talks in Damascus. ( AFP/HO/SANA )

ABC/wires

