Vlasiuk said this in a televised interview while discussing Russia's shadow fleet and the effectiveness of sanctions imposed by other countries, according to an Ukrinform correspondent.

"Globally, approximately 700 Russian vessels – ships that transport Russian oil – are currently under sanctions. Of those, roughly half have stopped such operations," he said.

Vlasiuk explained that for many of the remaining vessels, being placed on sanctions lists creates difficulties in operating anywhere other than Russia, China and India. At the same time, it can increase their risk of becoming subject to another type of sanctions that Ukraine's Defense Forces have successfully imposed.

"Therefore, I would advise no one to continue transporting sanctioned Russian oil – or liquefied gas, for that matter," the commissioner said.

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He stressed that the Ukrainian authorities are monitoring all attempts to expand or increase the size of Russia's shadow fleet.

"Every day, we see new information about a vessel changing its flag or another new voyage by a new vessel. All of this is recorded very quickly, becomes visible immediately, and relevant proposals to expand sanctions lists are promptly submitted to our partners. And, by the way, I think we will soon have a small sanctions package specifically targeting the shadow fleet," Vlasiuk said.

Asked what politicians or senior officials lose when sanctions are imposed on them, Vlasiuk said the main impact is on their business interests.

"If you are a major Russian oligarch with global business interests, sanctions make all your assets and your entire business toxic. That simply doesn't work. It confines you to operating only within the framework of Russia and, to a limited extent, India, China, Iran and North Korea. These are the countries where you can operate and do business – and perhaps Africa more broadly. But you can no longer rely on the usual global tools and services," he said.

Vlasiuk noted that for some oligarchs, sanctions also affect their reputation and create certain everyday inconveniences – such as being unable to visit their favorite berth in Cap-Ferrat or similar destinations.

As reported, the U.S. government recently sold two Russian-flagged sanctioned oil tankers, Era and Lileo, for scrap after they were detained several days following a U.S. operation in Venezuela.