S-300 missile system
S-300 missile systemReuters

The sale of Russian S-300 missiles to Iran may not take place, after all, the Arabic-language London-based Al Quds Al Arabi newspaper reported on Thursday. 

According to Al Quds Al Arabi, the two sides have not yet signed the contract for delivery of the Russian missiles to Iran, with the dispute centering on the deal's cost.

Last week, Iranian Defense Minister Brigadier General Hossein Dehghan claimed Tehran and Moscow have already reached an agreement on the terms of the deal, and could even formalize the purchase as early as this week, according to Iran Students News Agency (ISNA).

The missiles were to be an enhanced version of the S-300, with upgrades that would enable Iran to protect its nuclear research installations.

A previous Russian contract to sell Iran the S-300 system by 2010 fell through due to diplomatic pressure surrounding sanctions on the Islamic Republic.

However, with the signing of the recent nuclear deal - which includes an astonishing commitment to help Iran protect its nuclear facilities against an attack - Moscow had revived the sale.

But the Thursday report quoted an Iranian official visiting Russia as saying that “the two sides have failed to agree on the price, so the deal has not been signed.”

The official added that all other issues had been worked out, and that price was the only thing preventing the completion of the deal.