“Pre-conflict, it was pretty rare for Indian refiners to process Russian crude,” says Alan Gelder, refining professional at Wood Mackenzie. “Now, about one in 5 barrels of the crude oil that they course of is Russian.

“They [Indian refiners] have at all times exported to Europe, however they’re exporting extra now as a result of it’s extra enticing as Europe’s diesel costs are increased: it’s shorter of diesel due to the Russia-Ukraine battle.

“A big chunk of that diesel they produce now will be based on Russian crude oil.”

Steve Sawyer, director of refining at Facts Global Energy, says India and China “are exporting diesel – and some of it will have come from Russia.”

He stresses that Western restrictions on Russian oil weren’t designed to cease Russian oil exports altogether, due to their significance to the worldwide market.

The UK solely banned Russian oil and diesel imports on December 5. Under these guidelines, an imported barrel is deemed to have come from the final nation the place “substantial processing” passed off.  

This implies that crude oil from Russia that’s refined into diesel elsewhere, corresponding to in India, can completely legitimately be imported into the UK. The rule stems from longstanding tax guidelines, although campaigners worry it quantities to a loophole that helps Russian coffers.

Seven shipments from Jamnagar have arrived within the UK for the reason that ban on Russian oil and diesel imports got here into drive final month.

Louis Wilson, senior campaigner at Global Witness, mentioned: “Exploiting this loophole by bringing Russian oil within the again door places cash within the Kremlin’s pocket, violates the spirit of the UK’s embargo and undermines BP and Shell’s condemnation of the war in Ukraine.’’

Shell mentioned: “Shell made its choice to withdraw from all Russian hydrocarbons with conviction. We are delivering on this, in step with steerage from European governments, together with the UK, and in full compliance with sanctions, relevant legal guidelines and rules.

“Under continued guidance from such governments and through our tight internal controls, including strict no Russian-origin product contract clauses with suppliers, we are seeking to avoid fuels that may contain products refined in Russia.”

BP mentioned: “BP takes compliance with sanctions and export controls very critically and seeks to adjust to all relevant regulatory frameworks world wide. We proceed to have very strict processes and controls for sustaining compliance with relevant commerce sanctions, together with the UK’s Russia sanctions.

“We conduct thorough checks on all trading counterparties and certificates of origin and other documents are used to evidence the origin of products.”

A Government spokesman mentioned: “In light of Putin’s illegal invasion of Ukraine and weaponisation of energy, the Government has taken steps to end all imports of Russian fossil fuels including a ban of oil and oil products. Importers must be able to provide proof that goods are not of Russian origin.”

Trafigura, PetroChina and Essar didn’t remark.