The latest US sanctions targeting Russian and Iranian oil could significantly disrupt Russia's oil supply chains, the International Energy Agency (IEA) said in its monthly report on Wednesday.

The new US sanctions on Iran and Russia announced last Friday, target entities responsible for over one-third of Russian and Iranian crude exports in 2024.

"The new measures could result in a tightening of crude and product balances," the IEA said.

Washington's latest sanctions package includes over 160 tankers, which the IEA estimates transported about 22% of Russia's seaborne oil exports in 2024.

The agency highlighted the effectiveness of earlier vessel designations, saying they had "reduced the activity of designated tankers by 90%."

The US Treasury on Friday imposed sanctions on several vessels involved in transporting Iranian oil, as part of a broader effort to disrupt Russia's network of ships evading US-led energy sanctions.

Of the 183 blacklisted vessels, eight were identified as having transported both Russian and Iranian oil, the Treasury reported.

"Several of the vessels sanctioned today have shipped not only Russian oil but also sanctioned Iranian oil," the Treasury said.

The vessels are part of a "shadow fleet," described by the Treasury as a network using "high-risk shipping practices" to avoid detection.

Many of these ships have been involved in transporting Russian oil at prices exceeding the $60-per-barrel cap imposed by G7 countries, the Treasury added.