Deadly toxins that were to have been removed from Syria by 31 December under an international effort to rid the country of its chemical arsenal have not yet been delivered to port to be put on ships, a senior Russian diplomat has said.
Head of the Russian Foreign Ministry's disarmament department Mikhail Ulyanov warned that toxins were still being packed before a potentially hazardous road journey.
Ingredients to make sarin, VX gas and other agents are to be taken to the port of Latakia in northern Syria from where they will be shipped abroad for destruction.
"The removal has not yet begun," Mr Ulyanov said.
Syria has agreed to abandon its chemical weapons by June under a Russian deal agreed with the US.
The agreement followed international outrage after a 21 August sarin gas attack that western nations blamed on President Bashar al-Assad's government, but which he denies.
Damascus agreed to transport the "most critical" chemicals including nearly 20 tonnes of mustard nerve agent out of Latakia by 31 December to be safely destroyed abroad away from the war zone.
But the head of the global chemicals weapon watchdog - the Organisation for the Prohibition of Chemical Weapons (OPCW) - said earlier this month that the deadline could be missed.
Russia - which has given Assad crucial support during almost three years of civil conflict in Syria - airlifted 75 armoured vehicles and trucks to the Middle Eastern nation last week to carry chemicals to Latakia.
Syrian government forces took control of a key highway connecting Damascus to the coast earlier this month but Mr Ulyanov warned the trip could still be treacherous.
"They will have to be taken on dangerous roads, there are several dangerous stretches," he was quoted by Russia's RIA news agency.
He also said experts from several countries, the United Nations and OPCW had reached a "common understanding of the main points" of a plan to get the toxins from the port into international waters, but gave no details.
Mr Ulyanov said that while they are in Syrian waters, Russian and Chinese warships would escort the Danish and Norwegian container ships that are to carry the toxins away for destruction further from the war zone.