Deputy Foreign Minister Sergei Ryabkov said details provided by the Syrian government would bolster claims supported by Moscow that President Bashar Assad was not responsible for the August 21 attack, which the United States says killed more than 1,400 people.
"We believe that this will strengthen evidence that the rebels were involved in using chemical weapons," he said in comments carried by Russia's Itar Tass state news agency.
Ryabkov, whose country is a major ally of Syria, also accused the United Nations of producing a biased report on the attack.
"To put it mildly, we are disappointed by the approach of the UN Secretariat and the UN inspectors, who compiled their report selectively and incompletely," Ryabkov told the RIA Novosti news agency.
Meanwhile Wednesday, the New York Times reported that the UN report implicated Assad's elite forces in the firing of the deadly gas that killed hundreds.
While the UN inspectors' report wasn't mandated to and did not report on who fired the deadly gas it did indicate the directions from which two rocket strikes came, which according to the report in the Times, leads back to Mount Qasioun in Damascus where two of Assad's elite units – the Republican Guard and the Fourth Division are stationed.
Assad's forces had fired conventional weapons from the same site in the past, the New York Times reported.
Ryabkov argued that the UN report was "politicized and one-sided" as long as it was based solely on the August 21 attack and did not include findings about three other alleged chemical attacks.
The UN defended the report, saying its conclusion that rockets loaded with sarin gas were used in an Aug. 21 attack should not be questioned. "The findings in that report are indisputable," UN spokesman Martin Nesirky told reporters. "They speak for themselves and this was a thoroughly objective report on that specific incident."
Ryabkov met Assad in Damascus where the latter praised Moscow's position on the Syrian crisis, according to the state news agency SANA.
Assad "expressed his esteem and that of the Syrian people for Russia's position supporting Syria in the face of a savage attack and extremist terrorism supported by Western, regional and Arab states," SANA reported.
Washington and Moscow at the weekend reached an agreement on Syria's chemical weapons, giving Assad's regime a week to provide full details about its stockpiles and until mid-2014 to dismantle this arsenal.
U.S. President Barack Obama has vowed to keep military options if Syria did not comply.
UN inspectors were due to head back to Syria "within one or two weeks" to continue investigations into the earlier alleged chemical weapons attacks, head of the UN team Ake Sellstrom said.
He told dpa that the team was to "complete the investigation that we interrupted in order to investigate the August 21" attack.
"There are three allegations, so it could mean three locations," Sellstrom added. "It depends what we finally choose."
The chemical weapons experts said in their report that UN Secretary General Ban Ki-moon ordered them to look into the August 21 incident first, which happened while they were in Syria to investigate earlier alleged chemical attacks.
Samantha Power, the U.S. ambassador to the UN, told the UN General Assembly Wednesday that "it defies logic" to think that the rebels would have carried out the attack, in an area which they themselves controlled.
Power called for a "robust, binding" Security Council resolution to implement the U.S.-Russian accord, which plans to put Syria's chemical weapons under international control, and destroy them.
NATO chief Anders Fogh Rasmussen, meanwhile, said he believed "the credible threat of military action" contributed to push diplomatic efforts on eliminating chemical weapons in Syria.
To "keep momentum in the diplomatic and political process, the military option should still be on the table," Rasmussen said after talks with British Prime Minister David Cameron in London.
Rasmussen added it was key that the UN Security Council quickly adopts a "firm resolution" to ensure the elimination of Syria's chemical weapons in line with the U.S.-Russian deal.
Russia, however, insists that the planned resolution will not mention the use of force under Chapter 7 of the UN Charter.
Moscow argues that the accord reached with the United States says that such a threat would only be contained in a later resolution, if Syria is found to be not complying with the chemical weapons convention.
Meanwhile, Germany joined other Western nations in blaming Assad's forces for last month's chemical attack and called for those responsible to be brought before the International Criminal Court.
"The evidence clearly points to the Assad regime being responsible for breaking this taboo," said German Foreign Minister Guido Westerwelle in Berlin.
On the ground in Syria, a pro-opposition watchdog said that Kurdish fighters had expelled al-Qaeda linked groups from a Syrian village near the Turkish border after days of fighting.
The Kurdish People's Protection Units (YPG) forced fighters from the Islamic State in Iraq and the Levant out of Olouk, to the east of the contested border town of Ras al-Ain, the Syrian Observatory for Human Rights said.
At least 17 Islamists and four YPG insurgents have been killed since the fighting for control of Olouk began Monday, the Britain-based Observatory said.
Radical Islamists, fighting to oust Assad's regime, and Kurdish insurgents have repeatedly clashed in recent months.
Kurds, who have been marginalized by the Syrian regime for years, are trying to keep their regions from falling into the hands of Islamist militants.
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