Russia has begun transporting explosives, ammunition and drone components to Iran across the Caspian Sea as Tehran works to replenish weapons stocks depleted during its conflict with the United States and Israel.

The shipments provide Iran with a direct supply route from Russian territory at a time when Tehran is seeking to restore its missile and drone capabilities, NBC news reported.

The Caspian Sea is bordered by Russia, Iran, Azerbaijan, Kazakhstan and Turkmenistan. Western naval forces do not operate there, making shipments between Russian and Iranian ports considerably harder for the United States or its allies to intercept.

The route has already drawn military attention as Israel struck the Iranian Caspian port of Bandar Anzali in late March. However, the shipping activity resumed after the attack.

The reported Russian deliveries point to a significant reversal in the arms relationship between Moscow and Tehran.

Iran emerged as a major military supplier to Russia following Moscow's full-scale invasion of Ukraine in 2022, providing Shahed attack drones that Russia subsequently deployed extensively against Ukrainian cities and infrastructure.

Tehran also transferred technology that helped Russia establish domestic production of Iranian-designed drones. Moscow later modified the aircraft and expanded production inside Russia.

More recently, military assistance has increasingly flowed in the other direction.

Russia had supplied drones to Iran and provided Tehran with satellite imagery, intelligence and targeting information for operations against U.S. positions in the Middle East.

The latest shipments are taking place as Iran attempts to replenish weapons expended or destroyed during its confrontation with the United States and Israel.

A 60-day ceasefire between Washington and Tehran agreed in June was extended for another two months in August. Tehran's objective is not simply to replace lost weapons.

Iranian officials are seeking to restore enough missile and drone capacity to impose substantially higher costs on U.S. and Israeli forces in any renewed conflict.

With the Caspian providing the two countries with a direct maritime link, Moscow can now help Tehran replenish key weapons stocks through a route largely shielded from Western naval power.

As The Gaze informed earlier, Ukrainian intelligence has identified evidence that Russia has been providing Iran with satellite imagery of U.S. military facilities and strategic sites in the Persian Gulf, and that Kyiv will share the data with its international partners.

Additionally, President Volodymyr Zelenskyy dismissed suggestions that an Iranian attack on Ukraine is only a future risk, arguing that Tehran effectively launched one by supplying Russia with Shahed drones, related technologies, and production licenses.