According to security officials, the UN inspectors were going to the hospital in the Mazzeh district of the Syrian capital, where victims of gas attacks are reportedly being treated.

The team of UN experts has this week been investigating the chemical gas attacks that reportedly took place in the suburbs of Damascus on August 21.

The inspectors left their hotel in UN-marked cars, accompanied by several vehicles belonging to Syrian army troops.

Syrian authorities accuse the foreign backed militants of having used poison gas on August 24 in Jobar, another Damascus neighborhood, to push back an army offensive.

State television said some soldiers had been asphyxiated, and showed images of barrels that authorities reportedly found in the area containing "very dangerous toxic and chemical materials".

The UN inspectors are due to leave Syria by Saturday morning, and will report straight back to UN head Ban Ki-moon.

As the five permanent members of the security council held a second emergency meeting on Syria in two days on Thursday evening, Ban Ki-moon, instructed the 20-strong inspection team to leave on Saturday, a day ahead of schedule.

Ban also announced that the team would report to him immediately on departure, raising the possibility that the UN could issue an interim report.

The inspectors had not been due to deliver their findings for a week at least, with the analysis of samples a painstaking task.

The demand for a rushed early assessment reflects the fraught atmosphere at the UN triggered by US threats to launch unilateral attack within days.

NJF/NJF