By CNN Staff
(CNN) -- Inspectors overseeing the destruction of Syria's chemical weapons have visited 21 of the 23 sites they want to inspect by a Friday deadline, but security concerns have prevented visits to the remaining two, the world's chemical weapons watchdog said Monday.
"Efforts ... to ensure the conditions necessary for safe access to those sites will continue," the Organisation for the Prohibition of Chemical Weapons said in a statement released Monday.
A joint OPCW-United Nations team is overseeing Syria's efforts to destroy its chemical weapons, which the country agreed to do earlier this year under international pressure. The U.N. Security Council resolution gives Syria until mid-2014 to destroy that arsenal, and charges inspectors with completing their initial inspections of all Syrian chemical weapons and storage facilities by November 1.
But Syria is in the midst of a civil war, presenting inspectors with significant challenges, including having to cross front lines and move through areas controlled by rebels. The OPCW previously has said that cooperation by rebels, in the form of temporary cease-fires to allow inspectors safe passage, would be key of deadlines are to be met.
Monday's statement by the OPCW came a day after the group said Syria met its Sunday deadline for submitting a plan to get rid of the chemical weapons. Damascus disclosed the 23 sites earlier this year.
On August 21 a chemical attack outside Damascus led the United States and its allies to call for military intervention in Syria's civil war -- a situation that was defused in mid-September, when Damascus agreed to a U.S.-Russian plan to give up its chemical weapons stockpile.
But the Syrian opposition has protested that the Syrian government has done nothing to stop the killing of civilians using conventional weapons.
According to the United Nations, more than 100,000 people have died in the Syrian conflict. It began in March 2011 when government forces cracked down on peaceful protesters during the Arab Spring movement and has morphed into a full-blown civil war.
A proposed conference in Geneva, Switzerland, between Syrian government officials and opposition leaders, intended to broker an end to the war, has been delayed several times, but is tentatively scheduled for the end of November.
CNN's Roba Alhenawi and Jason Hanna contributed to this report.
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