Russia's veto came after the investigation blamed Bashar al-Assad's government of carrying out sarin attacks on its own people.
A commander of the al-Qaeda linked group Tahrir al-Sham in a statement claimed the group shot down the plane with a shoulder-fired missile in rural Idlib province, according to security consulting firm and NBC News partner Flashpoint Intelligence.
The White Helmets, a volunteer rescue group, said three of its members and six others were injured in a chlorine gas attack in the Idlib town of Saraqeb on Sunday night.
The incident took place on the territory controlled by the Jabhat Fatah al-Sham terror group amid an ongoing military operation conducted by Syrian forces.
On Monday, dozens of air strikes and artillery fire battered Eastern Ghouta, according to the Britain-based Syrian Observatory for Human Rights.
Syria denies US claims it used chemical weapons against rebel-held areas
On Thursday, the Trump administration accused Assad of producing and using "new kinds of weapons" to deliver deadly chemicals. The group plans to publish information about chemical attacks to name and shame perpetrators and eventually sanction them.
U.S. Ambassador Nikki Haley said Russian Federation is blocking a probe of chemical weapons use and shielding Assad by preventing a Security Council statement condemning the use of chlorine on civilians over the weekend.
Russian Federation has launched a bombing campaign against rebel groups in Syria in support of the government of Syrian President Bashar al-Assad. "The pilot had enough time to announce he had ejected into the zone", the defence ministry said.
In December the Syrian army, backed by Iranian militia and Russian air power, launched a major offensive to retake Idlib, the last Syrian province still mainly under opposition control.
Russia's defence ministry regularly says it targets only hardline Islamist militants in Syria.
A Russian pilot who was forced to eject from his stricken jet over Syria killed himself with a grenade to avoid being captured by jihadists - as he shouted, "This is for our guys!" The province is also home to about a million displaced people from around Syria, and renewed fighting has displaced residents within Idlib in recent weeks.