Russia and Iran missile dispute..

Russia and Iran have been locked in dispute after Russia surprisingly refused to supply Iran with surface-to-air missile systems.

"Unless Tehran retracts its lawsuit over Moscow's refusal to deliver S-300 surface-to-air missile systems, Russia will take a tougher stand on the Iranian nuclear issue, the Kommersant newspaper reported on Friday.

"We have already made it clear to Iran that lawsuits are not helping the development of our relations,” the newspaper quoted a Russian presidential administration source as saying. “But our requests to retract these documents from court went unnoticed."

Moscow is prepared to stop supporting Tehran over its nuclear program, he said."

Read more on Russia Today.