Russia has made it final. They are not selling Iran S-300 anti-aircraft missile systems. But the Russians are still doing lots of business with Iran, and are quickly refunding the $166.8 million they had received from Iran as a pre-payment for the S-300s. The deal was worth over a billion dollars, and the Russian defense industry was not happy with this decision. However, there is a bright side for Russia. The Iran deal was cancelled after three years of pressure from Western nations, particularly Israel. The West wants to keep modern weapons away from Iran, and cut a deal with the Russians to transfer Western defense technology to Russia (via co-production deals). In return, the Russians do not sell high-tech weapons to Iran. Israel is arguing with Russia at the moment over sales to Syria. Israel believes that Syria, a client of Iran and broke, is used as a buyer for modern weapons that will end up in Iran. The Russians are opposed to this restriction, and the Israelis are threatening to halt cooperation unless the Syrians are cut off.
Meanwhile, Iran, in response to losing the S-300, announced that it had gone ahead and designed its own, which will have similar capabilities as the S-300. Now Iran regularly announces it has designed and built modern weapons (which it cannot buy overseas because of three decades of embargos). These weapons rarely show up, although some are seen in prototype form. Meanwhile, the S-300, and similar systems, have not been delivered because Western nations have told Russia and China that if they arm Iran with modern weapons, there will be consequences.
But an "Iranian" S-300 might be more likely. That's because last year, Iran sought to purchase the Chinese made HQ-9 anti-aircraft missile system. China buys a lot of oil from Iran, and is considered an ally. China is believed to have secretly supplied Iran with a lot of military technology. By not delivering actual weapons, China avoids a confrontation with angry Western nations.
China has been offering its HQ-9 system to foreign customers, as the FD-2000, for several years now. The Russians are not happy with this, given the amount of stolen S-300 technology believed to be in the HQ-9. Russia has been pointed in warning China not to export weapons containing stolen Russian tech. But the Chinese have done it, apparently believing there's really nothing the Russians can do about it. China, in this case, may have followed past practice and quietly sold Iran the technology for the FD-2000, and let them build their own, and call it whatever they want.
A decade ago, China began introducing the HQ-9 for use by its army and navy (on ships). Over a decade of development was believed to have benefitted from data stolen from similar American and Russian systems. The HQ-9 missile is similar to the U.S. "Patriot," while the radar apparently derived much technology from that used in the Russian S-300 system. The HQ-9 missile has a max range of about 100 kilometers, weighs 1.3 tons and has a passive (no broadcasting) seeker in the missile.
Most of the systems used by the army are mobile. Army HQ-9 brigades have a brigade headquarters (with a command vehicle, and four trucks for communications and maintenance), and six missile battalions (each with a missile control vehicle, a targeting radar vehicle, a search radar vehicle and eight missile-launch-vehicles, each carrying four missiles in containers).
Neither the S-300 or HQ-9 have been tested in combat. Most earlier Russian designed air defense systems performed poorly in combat. Even the Russian SA-6 missile systems, that Egypt used in 1973, which were initially a surprise to the Israelis, were soon countered, and did not stop the Israelis from getting through. While the best sales technique is to push the product's track record, you have to do just the opposite with Russian anti-aircraft missiles. Thus the Russians, and now the Chinese with their FD-2000, emphasize low price, impressive specifications, good test results and potential.