An American investigative journalist and political writer has implicated Saudi Arabia and Turkey in the deadly 2013 chemical attack in the Damascus suburb of Ghouta.
A US intelligence report confirmed that Saudi Arabia and Turkey were providing al-Nusra Front terrorists with the basic chemicals used for sarin gas, Seymour Hersh told Russia's RT television network on Saturday.
The sarin gas used in the Ghouta gas attack "was not the same as in the Syrian military," he added.
"The government knew from this very important intelligence report ... that there were two suspects – al-Nusra had the stuff and Syria had the stuff. Forget about having it analyzed – they knew right away and they only talked about one," Hersh said.
Western countries held the Syrian government responsible for the Ghouta assault that killed hundreds of people in August 2013 without any evidence.
A UN report said the substance concerned was the nerve agent sarin and the delivery system was ground-to-ground rockets.
Syria surrendered its entire chemical stockpile in 2013 to a mission led by the Prohibition of Chemical Weapons (OPCW) and the UN.
US ship brings chemicals to region
Separately on Sunday, a senior spokesman for the Iranian armed forces said that the US Navy's Cape Ray vessel carrying chemicals had docked at the coast of one of the Persian Gulf countries.
Brigadier General Abolfazl Shekarchi said the ship had recently been escorted into the region by an American warship.
The chemicals carried by the US ship are meant to be transferred to parts of Iraq and Syria, he said, warring of the possible consequences of such efforts.
"After suffering consecutive blows by the resistance front, the Americans have now resorted to dangerous ways to continue their presence in Iraq and Syria and justify their illegitimate presence in the region," Shekarchi said.
The news proves that chemical attacks in Iraq and Syria have been engineered and led by the Americans, he added.
The Western countries have used the alleged gas attacks in Syria as a pretext to target military positions inside the Arab country.