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By Louis Charbonneau and Michelle Nichols
UNITED NATIONS, Jan 28 (Reuters) - U.N. Secretary-General Ban Ki-moon suggested in a report on Tuesday that an operation to remove Syria's chemical weapons had been unnecessarily delayed and urged the government of Syrian President Bashar al-Assad to speed up the process.
Under a deal negotiated by Russia and the United States, Syria agreed to destroy its chemical weapons arsenal after an Aug. 21 sarin gas attack, which killed hundreds of people and led to threats of U.S. air strikes. The Syrian government and rebels blamed each other for the attack.
Ban said in a report to the U.N. Security Council, dated Jan. 27 but made publicly available on Tuesday, that a Dec. 31 deadline for removing Syria's worst chemicals had been missed. Syria has said the operation faces security challenges.
"While remaining aware of the challenging security situation inside the Syrian Arab Republic, it is the assessment of the Joint Mission that (Syria) has sufficient material and equipment to carry out multiple ground movements to ensure the expeditious removal of chemical weapons material," Ban said.
The Organization for the Prohibition of Chemical Weapons set the Dec. 31 deadline for the removal from Syria of the worst chemicals, which include components for making sarin and VX nerve agent. These toxins are supposed to be destroyed offshore on a specially equipped U.S. ship by March 31.
The rest of Syria's chemical materials are due to be transferred out of the country by Feb. 5 and destroyed by June 30. The operation is being overseen by a joint mission of the global chemical arms watchdog and the United Nations.
Syria's three-year civil war has killed more than 100,000 people and caused millions to flee, according to U.N. figures.
Ban's report was written before the joint mission said on Monday that a second shipment of chemical weapons materials had been transferred out of Syria, nearly three weeks after the first batch was removed.
DELAYS 'NOT INSURMOUNTABLE'
Ban said in his report that the first shipment represented a "small quantity" of the worst chemicals and that the entire operation was now behind schedule.
"In recent days I have spoken to the Syrian Arab Republic and other Member States concerned to express my concern regarding this delay," Ban said.
"The Director-General of the OPCW and the Special Coordinator (of the joint U.N.-OPCW mission in Syria) have similarly engaged Syrian representatives to persuade them to enable immediate removal," Ban said.
Western governments have been growing impatient with Syria's failure to follow up promptly on a first small shipment of chemical weapons and fear Damascus will miss a deadline to destroy all toxins by mid-2014.
"The delay is not insurmountable," Ban said.
"The 30 June 2014 deadline is still five months away," he said. "However, it is imperative that the Syrian Arab Republic now examine the situation, intensify its efforts to expedite in-country movements of chemical weapons material and continue to meet its obligations."
The U.N. Security Council adopted a resolution in September on the operation to dismantle Syria's chemical weapons program, but it did not threaten automatic punitive action against Assad's government if it does not comply.
Eliminating Syria's chemical weapons under tight deadlines amid a civil war was overly ambitious from the beginning, some experts have said. Syria's toxic stockpile is spread over storage sites across the country and the chemicals must be transported by road to the port of Latakia. (Editing by Mohammad Zargham)