The United States is preparing to impose sweeping sanctions on Russia's two largest oil companies in a move expected to deal a major blow to Moscow's energy revenues and its vast network of shadow tankers, The Telegraph reported on Tuesday.

The measures, due to take effect later this month, mark the first time Washington has directly targeted Russian oil exports rather than capping their price or restricting insurance coverage.

The sanctions include the threat of secondary penalties on banks and financial institutions that facilitate payments for Russian crude — a step analysts say could severely disrupt the country's global trade.

Data from maritime intelligence company Windward AI show that attempts to evade Western restrictions have gone up sharply this year, with GPS-jamming incidents rising by 510% since January and more than 1,000 ships currently operating under false flags.

"In my 25 years of reporting on Russia and global oil flows, I've never seen anything like this," Michelle Bockmann of Windward AI told The Telegraph.

Many of these vessels form part of Russia's so-called "shadow fleet" — hundreds of older tankers operating outside Western insurance and tracking systems.

They routinely carry out ship-to-ship transfers of crude in international waters off Cyprus, near the Suez Canal, and off Oman's coast to disguise the oil's origin before delivery to buyers in India, China, and Turkey.

Enforcement of sanctions has tightened this year, with the U.K. and the European Union expanding their blacklists to include more than 1,000 vessels.

But until recently, the Trump administration had refrained from adding new designations, allowing some Russian-linked ships to continue operating freely.

Data from energy analytics company Kpler show that vessels hit by U.S. sanctions see activity decrease by 74%, compared with just 31% for those sanctioned by the U.K. or EU.

The new measures have already started to reshape the market. Major Indian refineries and Chinese state oil firms have suspended purchases of seaborne Russian oil due to compliance concerns.

Analysts say the move could mark a turning point for Russia's wartime economy.

"If the U.S. follows through on secondary sanctions, it could paralyze half of Russia's oil export system," Kimberly Donovan of the Atlantic Council told The Telegraph.

With oil prices steady and global supply relatively abundant, Washington appears willing to test how far it can push Moscow's oil trade without destabilizing markets.

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