Syria has failed to meet another key deadline for turning over its chemical weapons stockpile as part of an internationally brokered agreement.
Under a February 5 deadline set by the Organization for the Prohibition of Chemical Weapons (OPCW), Syria was to have given up its complete stockpile.
Syria has so far sent only two shipments of chemicals to be destroyed, amounting to less than five percent of its stockpile.
The OPCW says Damascus is not doing everything it can to meet that timetable.
Last week, the world body called on Syria to "pick up the pace".
On Tuesday, Russian officials said Syria is preparing a new schedule and will remove a large shipment of chemical weapons later this month.
The OPCW has set a final deadline of June 30 for Syria to remove all its chemical weapons.
The deal, brokered by the United States and Russia, follows last August's chemical weapons attack in the suburbs of Damascus that left hundreds dead. Syrian President Bashar al-Assad denied responsibility for the attack but agreed in September to hand over his chemical weapons supply.
Syria's conflict began in March 2011 as peaceful protests against the government before spiraling into a civil war that the U.N. says has killed well over 100,000 people and forced nearly 9 million from their homes.
On Tuesday, the United Nations released a report detailing the "alarming impact" of the conflict on the country's children.
In the report issued to the Security Council, U.N. Secretary-General Ban Ki-moon says government forces have killed countless kids, arrested and tortured children and kept them from accessing schools and health care.
The report says opposition fighters have used child soldiers in operations that resulted in casualties, including children, and engaged in summary executions of children as well.