An international inquiry has identified two Syrian Air Force helicopter squadrons and two other military units it holds responsible for chlorine gas attacks on civilians, a Western diplomat told the Reuters news agency on Friday.
The finding by the United Nations and the Organization for the Prohibition of Chemical Weapons (OPCW), the global chemical weapons watchdog, is based on Western and regional intelligence, the diplomat added.
"It was the 22nd Division, the 63rd Brigade and the 255 and 253 squadrons of the Syrian government," the envoy said.
The identification of specific military institutions responsible for attacks could strengthen a push by some Western members of the UN Security Council for a robust response, focused on sanctions and accountability, noted Reuters.
A UN-led investigation recently blamed the Syrian regime for at least two chemical attacks, one in 2014 and another in 2015.
President Bashar Al-Assad's government has repeatedly denied using toxic gas on the battlefield, and argues that claims that it used chemical weapons are only meant to "serve political agendas".
Responding to the new finding, a Syrian military source told Reuters, "The Syrian state ... and we, the Syrian Arab army, have said more than once that the army has not and will not use any banned weapon, especially chemical or poison weapons."
"This issue is completely void of truth. We consider the United Nations to be a tool in the hands of some countries which support terrorists," the source said, adding that the UN had not responded to Syrian requests to investigate alleged use of chemical weapons by insurgents.
The year-long joint UN and OPCW inquiry, which is investigating reports of attacks between April 11, 2014 and August 21, 2015, is due to submit its fourth report to the UN Security Council next week.
It is unclear whether the fourth report will assign blame to individuals as the third one did. The inquiry has focused on nine attacks in seven areas of Syria, where a separate OPCW fact-finding investigation concluded that it is likely chemical weapons have been used.
Eight of the attacks investigated involved the suspected use of chlorine. The inquiry said it had not yet been able to reach a conclusion in six cases, though it said three of those cases warranted further investigation.
"At least two others were chlorine and were carried out at the hands of the Syrian Air Force," the diplomat said. "There is no indication that any opposition groups used chlorine."
Syria agreed to destroy 1,300 tons of declared chemical weapons in 2013 under a deal brokered by Moscow, Damascus's main international backer, and Washington, which supports the Syrian opposition.
In a separate confidential report seen by Reuters, OPCW inspectors concluded in July after 16 visits to Damascus since April 2014 that Syria had failed to explain "scientifically or technically" the discovery of banned agents by its inspectors, including sarin and VX nerve agents.
Meanwhile, dozens of people had to be treated for breathing problems following a barrel bomb attack in the city of Aleppo last week.
Following the attack, in the rebel-held Sukkari district of Aleppo city, the opposition accused the regime of dropping chlorine gas.
The Syrian government once again denied using toxic gases, saying, "The real criminal in all cases in which gases were used was armed terrorist groups who carry out the instructions of their masters in order to defame the achievements of the Syrian Arab Army."
“Terrorist groups” is the term used by President Bashar Al-Assad’s regime to describe all rebel groups fighting to oust him, including both Western-backed rebels and jihadist groups such as the Islamic State (ISIS).
Chlorine's use as a weapon is prohibited under the 1997 Chemical Weapons Convention, which Syria joined in 2013.
If inhaled, chlorine gas turns to hydrochloric acid in the lungs and can kill by burning the lungs and drowning victims in the resulting body fluids.
The new finding, blaming specific military units, could set the stage for a showdown at the Security Council pitting the United States, Britain and France against Russia and China.
Beijing and Moscow have veto powers as permanent Council members and have protected Syria's government from action by blocking several resolutions, including an attempt to refer the situation in Syria to the International Criminal Court.
(Arutz Sheva’s North American desk is keeping you updated until the start of Shabbat in New York. The time posted automatically on all Arutz Sheva articles, however, is Israeli time.)