A base in Ochakov, in Southern Ukraine, on the Black Sea, that was supposed to serve the British and Americans was obliterated.

Source

UPD 2024: I at first thought this is a typical Russian hyperbole. I was kind of stunned that this was the first thing Russia destroyed in the war. Kinda reminds me of this video of Russian spetsnaz saying that the Kiev regime has been inviting NATO in…

I have found more info on the Ochakov base.

During Yushchenko’s presidency and the again after the Maidan, and meanwhile the US wanted to get Ukraine into NATO. Even without NATO membership, the US began building a military base near Odessa, without limit to the kind of weapons that could stationed there. After completion, the base could be used for launching rockets with 6-7 minutes flight time before reaching destination. Russia could then be blackmailed in almost any question. Russia wrecked it in the first days of the operation in 2022.

“In the future, the base should be a command centre for the Ukrainian Navy” -explains Oleg Zhdanov for Apostrophe. “In the time of peace it will serve as a training centre for the naval forces of NATO countries and Ukraine. This is a training and material base for command of the navy”

Source (2017)

Komsomolskaya Pravda wrote about US and UK presence in Ukraine in 2021. The blue points are where troops were openly deployed, the red points indicate conspicuous deployments. Yavoriv base was also bombed, and there have been reports of NATO officers being besieged in Mariupol.