Moscow's top envoy to Seoul rejected accusations by the United States that its recent military intervention in Syria targets Western-backed rebel forces, saying they are "pure fabrication."

Speaking in an exclusive interview with Yonhap News Agency on Wednesday, Ambassador Alexander Timonin said Russia's air strikes in Syria are aimed at combating the Islamic State and other terrorist groups, a claim that has been regarded with suspicion by Washington and other Western powers since the intervention began on Sept. 30.

"Unfortunately, the actions of the U.S.-led coalition have been extremely ineffective in Syria," Timonin said. "As a result of the operations of this alliance, the so-called Islamic State and al-Nusra Front and other terrorist groups have only expanded their influence and territory."

Russia's intervention, four years after the Syrian civil war broke out, was a legitimate response to a call for help from the Syrian government, which was based on Russian laws, the U.N. charter and relevant international laws, he added.

"The purpose of our air strikes in Syria is to prevent the collapse of Syria's state system and to liquidate the source of terrorism there," the envoy said. "Claims by U.S. leaders that the Russian air force is intentionally striking rebel forces backed by the West are a pure fabrication."

Timonin accused Washington of failing to respond to Moscow's request to share any information that could help Russia strike the necessary positions and avoid those that should be avoided. Russia and the U.S. share an understanding on the need to fight international terrorism, he said.

He also stressed that Moscow does not support Syrian President Bashar al-Assad personally but believes that Syria's defeat to terrorist groups would not help establish democracy in the Middle East.

"That is why Russia's approach is to first destroy the Islamic State and then to let the Syrian people choose their president through their free expression of will."

Assad made a surprise visit to Moscow on Tuesday and held talks with Russian President Vladimir Putin. It was his first overseas trip since the civil war broke out in 2011. (Yonhap)