Iran and Russia are negotiating a deal for Moscow to supply Tehran with advanced S-400 air defence systems, which could help the Islamic Republic rebuild its weakened military defences following US and Israeli strikes, The Telegraph has reported. A senior Iranian official told the newspaper that Tehran was “optimistic” that Russian President Vladimir Putin would finally agree to deliver the long-sought weapons.
Iran’s Supreme Leader Mojtaba Khamenei reportedly sent security chief Mohsen Rezaei to Moscow on Thursday with a personal letter to Putin. According to the official, the main demand in the letter was the supply of the S-400 systems.
The reported negotiations appear to contradict US President Donald Trump’s claims that Russia is not providing assistance to Iran.
Following his meeting with Putin, Rezaei said: “Important regional issues were discussed with Putin, and significant conversations took place regarding the post-war period and regional security arrangements.”
The two sides also discussed plans to build a new gas pipeline connecting Russia and Iran.
Iran Seeks S-400 Systems To Rebuild Air Defences
The S-400 deal would mark a significant development in Iran’s efforts to strengthen its military capabilities after repeated US and Israeli attacks severely damaged its air defence network.
The strikes exposed Iran’s inability to adequately protect its airspace, nuclear facilities and senior military and political figures, including former Supreme Leader Ali Khamenei, who was killed in the conflict.
Moscow has discussed the possibility of selling the advanced systems to Tehran for years but has so far stopped short of delivering them. Analysts and regional officials cited by The Telegraph said Russia had been cautious about damaging its relations with Israel and other countries in the region.
There are also questions over whether Moscow can afford to supply the systems. Russian air defences are under sustained pressure from Ukrainian long-range drone and missile attacks targeting refineries, airbases and other infrastructure. This could leave Russia with limited capacity to provide Iran with some of its most advanced military equipment.
Iran has already secured several weapons deals with Russia as part of broader efforts to prepare for a prolonged confrontation with the US and preserve the Islamic Republic.
Leaked Documents Reveal Russian Missile Deal
The latest negotiations come as leaked Russian defence industry documents have revealed that Moscow has been manufacturing helicopter-launched missiles for Iran.
According to the documents reviewed by The Telegraph, Russian state-owned factories are producing specialised missile-launch equipment for Tehran under an export contract identified by the code “K-10”. One of the documents identifies the code as referring to Iran.
The equipment includes launch units for the LMUR, also known as Product 305, a precision-guided missile.
A delivery schedule from 2024 allocated power units for 90 twin-rail launchers to a Russian manufacturing plant, with Iran listed as the end customer. The equipment was scheduled to be shipped by December 2025.
The revelations point to growing military cooperation between the two countries, even as Moscow has yet to commit to supplying the S-400 systems.
Iran’s Pre-War Plan To Deepen Military Ties With Russia, China
The discussions also come against the backdrop of Iran’s efforts to strengthen strategic partnerships with Russia and China ahead of the conflict with the US and Israel.
Confidential documents reviewed by The Telegraph show that a secret Iranian parliamentary committee had drawn up recommendations on how the country could withstand a major war with Washington.
The proposals, prepared before the conflict began in February, called for closer military cooperation with independent global powers, particularly Russia and China, as well as improvements in Iran’s air defences, missile capabilities and drone programme.
The document argued that Iran’s ability to resist foreign pressure over four decades showed that attempts to bring about its collapse from within were unlikely to succeed. “The Iranian people’s resistance to foreign pressure over the past four decades has shown that a strategy of ‘collapse from within’ cannot easily succeed,” it said.
Trump has repeatedly played down the extent of Russian and Chinese assistance to Iran, even as his administration has pursued direct engagement with Moscow over the war in Ukraine.
