A US government report concluding Syrian army has used chemical weapons against militants in Syria “is fabricated, ” a senior Russian lawmaker says.

“Information about the usage of chemical weapons by[Syrian President Bashar] Assad is fabricated in the same way as the lie about[Saddam] Hussein ' s weapons of mass destruction[in Iraq], ” Alexei Pushkov, head of the Russian lower house of parliament’s international affairs committee, said on Twitter on Friday.

US intelligence reports presented to the UN and the international community prior to the US - led invasion of Iraq in 2003 claimed Saddam Hussein’s regime possessed weapons of mass destruction including nerve agents, ballistic missiles and a nuclear weapons program.

The US claimed the threat posed by those weapons justified the invasion of Iraq, but after the country was occupied, the alleged weapons of mass destruction were never found.

President Obama “is going the same way” as former President George W. Bush did then, Pushkov said.

The White House claimed on Thursday it now believes with “high confidence” that Syrian government forces have used chemical weapons many times during the two - year conflict there, and vowed to boost US aid to the armed opposition fighting to remove Assad from power.

White House Deputy National Security Adviser Ben Rhodes said Obama had decided to provide further support, including military support, for Syrian opposition forces as a result of its conclusion that government forces has used such chemical weapons.

Rhodes declined to clarify whether this support would entail providing arms to the Syrian opposition, but said US aid to armed opposition on the ground would differ greatly “in scope and scale” from assistance Washington had previously provided to the rebels. The US goal, Rhodes said, is to “strengthen their effectiveness. ”

Syrian government officials, however, say opposition forces have used chemical weapons against government troops and people several times, including an attack outside the northern city of Aleppo in March.

On May 10, a member of the UN Independent International Commission of Inquiry on Syria, Carla Del Ponte, said the militants had used the nerve agent Sarin which UN Resolution 687 classifies as a weapon of mass destruction.

She added that her panel had found no evidence yet showing that government forces have used chemical weapons.

US chemical arms report on Syria fabricated: Russia