The UN chemical weapons inspectors are expected to return to Syria on Wednesday , according to the Russia's government.
Deputy Foreign Minister Sergei Ryabkov said the team would look into the alleged use of chemical weapons at Khan al-Assal, Sheikh Maqsoud and Saraqeb, according to a BBC report.
The inspectors were previously preparing to investigate the sites when chemical weapons were fired at suburbs of Damascus on 21 August, killing over 1,400 people.
Last week, the UN report on the chemical attack confirmed that the nerve agent sarin was used in Damascus.
The inspectors were not asked to determine who was responsible for the artillery rockets (which contained the sarin) which hit parts of Damascus, but Western powers point the finger of blame towards Syrian government force s.
The Syrian and Russian governments have challenged them to present firm evidence , and instead alleged that rebels were responsible , BBC said.
UN war crimes investigators say there have been 14 alleged cases of chemical weapons being used in the Syrian uprising against President Bashar Assad, which began as peaceful protests in 2011.
In July, Damascus granted permission to UN inspectors to visit Khan al-Assal, Sheikh Maqsoud and Saraqeb, where both sides have accused each other of using chemical weapons in warfare, BBC reported.
Following several delays, the team arrived in Damascus on 18 August and were preparing to travel north to conduct on-site inspections when the first reports of the Ghouta attack emerged.
After taking environmental, chemical and medical samples, and interviewing survivors and doctors between 26 and 29 August, the UN inspectors flew out of Syria because it appeared increasingly likely that the US would launch punitive military action, according to the BBC.
The threat of a US-led military strike on Syria had diminshed by 14 September when the US and Russia agreed a framework for the destruction of Syria's stockpile of chemical weapons by mid-2014 , BBC said.
On Tuesday, Deputy Foreign Minister Ryabkov told the Russian parliament that the UN inspectors were expected to resume their work imminently.
"We are pleased that our persistent calls for the return of UN experts to Syria  for the investigation of other episodes have borne fruit," he said, according to the BBC.
Last week, he criticised  the UN inspectors' report, saying it was "distorted" and "one-sided", and based upon "insufficient" information .