The United States and its Western allies said Wednesday they would tighten loopholes that have allowed Russia to evade a cap on its oil price, aiming to reinforce a policy aimed at curbing energy revenues that the Kremlin has used to finance the war. from Ukraine.

The Group of Seven countries and Australia, known as the “price cap coalition,” agreed last year on a U.S.-led plan to limit what Russia can charge for its oil exports to $60 a barrel. Initially, the untested policy appeared successful in keeping Russian oil flowing while raising its export costs and reducing its energy revenues.

But in the months that followed, Moscow skirted the limit by developing a “shadow fleet” of tankers and finding alternative insurance and financing options, allowing it to sell oil at higher prices.

The price cap works by prohibiting Russia from accessing Western marine insurance and financial services that are key to its oil exports, unless its crude is sold below $60 a barrel. The policy relies on those insurers and financial service providers to verify the price of the oil being sold. But the verification process has not been effective and Russia has routinely been able to sell oil above that limit.

The actions announced by the Group of 7 on Wednesday will require oil shippers that use Western marine insurers and other companies that finance Russian oil exports to provide more frequent and rigorous documentation to those service providers about the content and prices of oil shipments. The coalition will also demand that other participants in the energy trading supply chain be prepared to provide more information about ancillary costs, such as shipping rates, that traders have been inflating to disguise the higher prices paid for energy. Russian oil.

“These changes will support implementation of the oil price cap and disrupt circumvention by reducing opportunities for bad actors to use opaque shipping costs to disguise oil purchased above the cap,” the price cap coalition said in a statement. announced on Wednesday. The group said the new requirements would “further complicate Russian exporters’ efforts to circumvent the price cap and deceive coalition service providers.”

The coalition said the price cap had been successful this year because global markets remained well supplied with oil and energy prices had remained stable. It also estimated that Russian tax revenue from exports of oil and petroleum products fell 32 percent from the previous year.

However, energy industry analysts have been less impressed with the cap, which essentially diluted Western embargoes on Russian oil in an effort to prevent global oil prices from soaring. Experts from the Center for Strategic and International Studies argued in an October report that the limit initially appeared to work because the $60 threshold was set above market prices, but that when global oil prices rose this year, exporters and Russian oil traders were able to easily bypass the lid.

“Oil prices have risen since July, exposing fatal flaws in price caps on Russian oil exports,” they wrotenoting: “Since mid-July, Ural crude oil from Russia has consistently traded above the peak price of $60 per barrel.”

The European Union and the United States have been taking steps this fall to crack down on price cap evasion.

The European Union’s latest sanctions package includes measures to restrict the sale of old transport vessels heading to Russia’s shadow tanker fleet.

The Treasury Department imposed new sanctions on Wednesday against a Russian-owned ship manager based in the United Arab Emirates that has been transporting Russian crude oil priced above $60. It also imposed sanctions on three unknown Russian oil traders who are based in the Emirates and Hong Kong and have been violating the rules.

Wally Adeyemo, deputy secretary of the Treasury, said the sanctions “demonstrate our commitment to upholding the principles of the price cap policy, which promotes the objectives of supporting stable energy markets while reducing Russia’s revenue to finance its war against Ukraine”.