U.N. Secretary-General Ban Ki-moon said on Monday that there is "overwhelming and indisputable" evidence that chemical weapons were used in the ongoing conflict in Syria.
After reviewing a report that U.N. inspectors handed in earlier on Monday, Ban called the use of chemical weapons a war crime but stopped short of directly blaming Syrian President Bashar al-Assad for the alleged attack, which the U.S. says left more than 1,400 people dead.
Ban further stated that the U.N. would support a resolution to remove Syria's chemical weapons from the country and put them under international control.
He said he approved of the framework Russia and the United States agreed to two days ago.
Ban also supported the U.S. and French view that there should be consequences if Syria fails to account for and eventually turn over its chemical weapons, but he did not specify that military action should be used.
Ban's statements are based on a report by U.N. scientists who visited neighborhoods outside Damascus in recent weeks. While in Syria, they interviewed more than 50 residents as well as medical personnel.
In areas where chemical weapons were suspected of being used, scientists found that 85 percent of blood samples tested positive for sarin gas. The investigators interviewed 36 people who showed symptoms of poisoning; almost all of them tested positive for exposure to sarin.
The investigators concluded, through environmental and biological tests as well as interviews with first responders and medical workers, that surface-to-surface rockets carrying sarin had hit the Ghouta suburb of Damascus.
They hypothesized that the rockets were fired when the weather was most conducive to sarin's having deadly effects.
"The downward movement of air would have allowed the gas to easily penetrate the basements and lower levels of buildings and other structures where many people were seeking shelter," Ban said, referring to the report.
According to his statement, the investigation team faced sniper fire and other dangers that prevented it from collecting data on other possible uses of chemical weapons. Still, the team had no doubt that chemical weapons were used on a "relatively large scale."
"The United Nations mission has now confirmed, unequivocally and objectively, that chemical weapons have been used in Syria," Ban said.
He said he hopes the U.N. Security Council will come to a unanamous solution to enforce the Russian and U.S. plan.
This is the latest step in support of a diplomatic solution to a standoff that nearly escalated into a U.S.-led punitive military strike against Assad's government.
But the details of any international solution are still murky. Russian Foreign Minister Sergey Lavrov balked earlier on Monday at the strong language used by U.S. Secretary of State John Kerry and U.S. allies in condemning Syria's government.