Tehran, Dec 11 (IANS): Iran's Supreme Leader Ali Khamenei said on Wednesday that the political upheaval in Syria was the result of a joint "plot" by the United States and Israel.

He made the remarks at a meeting with a group of people from different walks of life in Tehran while commenting on the latest developments in Syria, which led to the fall of President Bashar al-Assad's government, according to the footage of his remarks released by his website.

The Iranian leader said although "one of Syria's neighbours ... has played and is playing a clear role" in that regard, the main "factors, conspirators, plotters and command room" were in the United States and Israel.

He stressed, "We have evidence (for this), which does not leave any room for doubt", Xinhua news agency reported.

Dismissing speculations about the weakening of the resistance front in the aftermath of al-Assad's government collapse, the Iranian leader assured that the resistance would get stronger.

"This is the resistance. This is the resistance front. The more you pressure it, the stronger it grows; the more you commit crimes, the more motivated it gets; and the more you fight it, the more widespread it becomes," he said.

Khamenei added that those who attacked Syria had different objectives, noting that some of them in northern and southern Syria sought to seize land, and the United States aimed to strengthen its foothold in the region.

He said that time would prove that none of them would be able to achieve their objectives, emphasizing that the seized Syrian regions would undoubtedly be liberated by Syria's "brave" youths.

Al-Assad has resigned and arrived in Russia for asylum as his government collapsed on Sunday following a sweeping offensive by militant groups.