French permanent representative Gérard Araud says monitors will leave country unless unlikely new resolution is reached

The UN security council will probably not renew the mandate of its observer mission in Syria later this month, which would require it to pull out of the country, France's permanent representative to the organisation said on Thursday.

"I think the mission will disappear on 19 August," Gérard Araud said. The mandate of the UN supervision mission in Syria (Unsmis) expires on that date.

But Vitaly Churkin, Araud's Russian counterpart, criticised the Frenchman for declaring Unsmis effectively dead.

He made it clear Moscow would "strongly urge the secretary-general [Ban Ki-moon] to continue with the monitoring component" of Unsmis after 19 August.

In order for the monitors to remain in Syria after that date, the council would have to adopt a new resolution to that effect. Araud said it was difficult to imagine the council reaching agreement.

Ban is expected to deliver a report next week to the 15-nation council with recommendations regarding the future of Unsmis.

Given international mediator Kofi Annan's decision to step down at the end of the month, which was announced on Thursday, UN diplomats said the prospects for securing a diplomatic solution and a truce that could be monitored by Unsmis were not good.

The security council extended the three-month mandate of the UN observer mission in Syria for another 30 days last month. It will decide in a few weeks whether to extend it again.

Araud said the situation on the ground in Syria would have to improve significantly for the council to agree to keep Unsmis in place.

Some western diplomats say they are reluctant to keep the mission in Syria given that there is no truce for the observers to monitor and neither side in the conflict appears to want a diplomatic solution to the crisis. The US, they said, was most eager to end the mission's mandate.

The EU's humanitarian affairs commissioner, Kristalina Georgieva, said on Wednesday that the presence of Unsmis had been beneficial for aid delivery.

Araud described the security council as "irreconcilably deadlocked" on the issue of Syria because two of the five permanent veto-wielding members were too far apart in their views for the council to reach an agreement. He did not name the two states, but it was clear he meant Russia and the US.

Russia, along with China, has vetoed three resolutions on Syria that would have condemned the government of Syrian president Bashar al-Assad and threatened it with possible sanctions.

"The divisions are as great as ever," Araud said. "We can predict a clash. The security council is deadlocked. Three vetoes enable us to say that."

The US and the UK suggested it was Russia and China that undermined Annan's peace efforts by vetoing attempts to pressure Assad to halt his 17-month crackdown against an increasingly militarised opposition determined to oust him.

Russia said it was the western powers that undermined Annan.

The UN's 300 unarmed observers, whose role had been to monitor a failed 12 April ceasefire in Syria brokered by Annan, suspended most activities on 16 June because of increased risk from rising violence.

Half of the monitors have already pulled out, but diplomats said there were more than 70 civilian staff working on a political solution and monitoring rights problems.

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