Ukraine's President Volodymyr Zelensky charged Russia with supporting the Iranian regime on Saturday after Tehran warned Ukraine about possible missile retaliation for a strike on a vessel in the Caspian Sea.

This marks another instance highlighting the long-standing Russia-Iran cooperation that has spanned many years.

"I will direct our intelligence services to pass along details we hold about Russia's fresh support for the Iranian regime," Zelensky posted on X on Saturday. "From early July onward we have noted ongoing Russian satellite monitoring of Gulf nations and American military sites in the region."

"Those images then show up in Iran. There is a direct match between the Russian satellite pictures of these locations and Iranian strikes, both ahead of the attacks during planning and afterward to evaluate the harm caused," he continued.

"Just on July 19 and 20, four air bases came under Russian satellite scrutiny - two in Bahrain, one in Jordan, and one in Kuwait," the Ukrainian president stated. "The intent is obvious. No one anywhere should ignore the basic reality that harm seeks fresh paths to worsen and expand. Russia must be halted. This conflict must end. Sanctions on the aggressor must succeed."

'The two conflicts have now combined'

Yaroslav Trofimov, Chief Foreign Affairs Correspondent for the Wall Street Journal, also shared his view.

"The two conflicts have now combined. Iran reports that a Ukrainian drone strike on its vessel in the Caspian killed a crew member. Ukraine had previously stated it was hitting ships moving weapons between Russia and Iran across the Caspian," he noted.

The conflicts involve US actions against Iran and the fighting in Ukraine. Russia launched its invasion of Ukraine in 2022, while the US and Israel began strikes on Iran in February 2026.

One aspect of this overlap is Zelensky's assertion that Ukraine hit a ship carrying Iranian military supplies to Russia.

"We also secured strong outcomes with long-range hits in the Caspian Sea, including ships involved in military shipments with Iran as well as a naval vessel," he said. Iran stated the Ukrainian strike resulted in the death of one sailor aboard the ship.

The pro-government Tehran Times reported that Iran firmly denounced "Ukraine's strike on an Iranian commercial vessel in the Caspian Sea."

The account noted Iran's foreign ministry condemned the early Saturday Ukrainian strike on the vessel, which caused an explosion, the death of one sailor, and injury to another.

Iran asserts self-defense right following Caspian attack

It added that "the strike, confirmed by Ukrainian officials, represents a clear breach of Article 2(4) of the UN Charter and an aggressive act that could widen the regional fighting. Tehran, which has stayed out of the Russia-Ukraine conflict, urges the UN Security Council and European countries to hold Ukraine responsible for this unlawful action."

Iran maintains it holds a right to self-defense after the incident, even as it has continued supplying drones to Russia during the Ukraine conflict.

Iran and Russia maintain close ties on military and economic matters. In May, The New York Times observed that the Caspian region was gaining importance amid the Iran situation.

"The enclosed sea has gained fresh relevance, as Russia sends military and commercial supplies to help Tehran resist the US pressure."