The land-attack version of Neptune cruise missile has already been used to strike objects inside russia, as follows from a situational update published by the President of Ukraine Volodymyr Zelenskyi on March 15 afternoon after receiving reports from Commander-in-Chief Oleksandr Syrskyi.
"Today there were also reports on our missile program," Zelenskyi wrote on social media. "We have tangible results. The 'Long Neptune' missile has been tested and successfully used in combat. A new Ukrainian missile, a precise strike. The distance was one thousand kilometers. I thank our Ukrainian developers, manufacturers and military personnel. We continue our work to ensure the security of Ukraine.
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More details about the so-called "long Neptune" have not yet been made public, specifically regarding its production rates or when exactly this missile was used to strike russian forces. Although Defense Express reminds that in November 2024, Zelenskyi said Ukraine's missile production in general had crossed "the first hundred units."
The development of a long-range variant of Neptune was disclosed in late 2023 when the Ukrainian Deputy Minister of Defense, Lieutenant General Ivan Havryliuk, noted without details that work was underway on a "new modification" of the missile. It was then unofficially labeled the "long Neptune," referring not necessarily to its dimensions but range capabilities.
Unconfirmed reports about the Ukrainian Defense Forces already using a modified Neptune for strikes on russian military sites appeared earlier, in summer 2023. These reports claimed that this modification had a range of 400 km and a warhead of 350 kg; allegedly, it was this missile that destroyed an S-400 air defense system in the russian-occupied Crimea in August 2023.

In general, however, Neptune strikes on russia aren't too rare. The cruise missile system has been repeatedly used to strike at particularly important targets or facilities located on russian territory.
For instance, in January, Defense Express summarized the available data on Neptune strikes in 2024, and among notable targets were a base stockpiling Shahed-series kamikaze drones near the Eysk airfield and an equipment storage site near Kursk.
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