Senior Iranian officials have accused the US of supporting the Islamic State terrorist group and effectively forming an alliance with it, claiming that Tehran possesses documents to prove the allegations. No evidence, however, has yet been presented.

Deputy Chief of Staff of the Iranian Armed Forces Major General Mostafa Izadi on Sunday accused the US of supporting Islamic State (IS, formerly ISIS/ISIL), stating Tehran has evidence to back the bold allegations.

"We possess documents and information showing the direct supports by the US imperialism for this highly disgusting stream [IS] in the region which has destroyed the Islamic countries and created a wave of massacres and clashes," Fars news agency quoted Izadi as saying.