A high-ranking Russian official says Moscow is working to upgrade the S-300 surface-to-air missile defense system it plans to deliver to Iran, Press TV reported.
Vladimir Kozhin, President Vladimir Putin's aide on military and technical cooperation, said on Thursday that the Russian-built S-300 air defense system is to be modernized before being delivered to Iran, given the fact the original contract was struck a long time ago.
Last month, Yan Novikov, the chief executive of Russian state arms producer, Almaz-Antey, confirmed the removal of all restrictions on S-300 deliveries to Tehran.
"All restrictions have been lifted by the political authorities. When there is a contract, we will supply the system, including to Iran," Novikov said.
On April 13, Putin signed a presidential decree paving the way for the long-overdue delivery of the missile defense system to Iran.
The decision to deliver the missile system came after Iran and the P5+1 group of countries - the United States, France, Britain, China and Russia plus Germany - reached a mutual understanding on Tehran's nuclear program in the Swiss city of Lausanne on April 2.
Moscow had banned the delivery of the S-300 system to Tehran in 2010 under the pretext that the agreement it signed with Iran in 2007 was covered by the fourth round of the UN Security Council sanctions against the country over its nuclear program. The resolution bars hi-tech weapons sales to the Islamic Republic.
Iran's Deputy Foreign Minister for Arab and African Affairs Hossein Amir-Abdollahian said on May 25 that all issues surrounding the delivery of the S-300 system to Iran were progressing well, adding that the defense system would be delivered to Iran in the soonest opportunity possible.