Russians are registering concern over Moscow's recent cancellation of its deal to sell Iran the S-300 anti-aircraft surface-to-air missile defense system.

The move has prompted Tehran to ease away from Russia's influence, warned a daily newspaper that reported Moscow will lose millions of dollars for cooperating with the United Nations on Iran.

Russia nixed the $800 million deal last month in the wake of a new round of economic sanctions against Iran imposed by the United Nations Security Council.

The Russian daily Nezavisimaya Gazeta reported that Russia would also lose an additional $400 million in penalties for breach of contract – a sum the newspaper warned the country can ill afford to lose.

Moreover, Russia's refusal to deliver on its contract could push Tehran towards China as its main arms supplier, further depriving Moscow of a strong source of revenue, the Gazeta added. Iranian refusal to buy further military products from Russia could lead to an estimated loss of up to $500 million per year.

In June, the Islamic Republic threatened that Russia would be “held responsible” for the consequences of failing to deliver the surface-to-air missile systems, which were intended to defend Iran's nuclear sites from possible attack by Israel.

Tehran banned its airlines from using Russian-built Tu-154 airliners on domestic and international routes, and there were rumors that Russian pilots would be deported from the country.