Ukraine has waged a devastating campaign on the so-called Achilles’ heel of Russia’s oil refineries thanks to secret training from America’s CIA, it is claimed. US intelligence reportedly helped Ukraine develop a more targeted approach after previous drone strikes on the infrastructure had little effect.

Ukrainian forces have regularly struck Russia’s oil refineries during 2025, with the attacks ramping up in the second half of the year. The surge sparked fuel shortages in parts of Russia and soaring prices amid production issues which also reduced exports. The strikes cost the Russian economy up to £55 million per day, according to a US intelligence estimate.

The more concentrated campaign is said to have been devised in June after a meeting between US military officers and their CIA counterparts.

According to The New York Times, which said it spoke to more than 300 officials, officers and diplomats as part of its report, it was decided Ukraine should focus exclusively on oil refineries and target a coupler device identified by a CIA expert as a weak point.

It was found that wiping it out would leave a refinery shut for weeks, as the equipment was so difficult to replace or fix, the report said.

The US has reduced its support to Ukraine under the Trump administration.

It is claimed that when Donald Trump ordered a military aid and intelligence freeze in March, the US President allowed the CIA to continue sharing information with Kyiv.

CIA director John Ratcliffe reportedly explained to Mr Trump the danger facing CIA officers in Ukraine.

Mr Trump is said to have been supportive of the US’ secretive role in disrupting Russia’s oil network.

The New York Times, citing officials, reported Mr Trump said it gave him deniability and leverage over Vladimir Putin as talks on ending the war made slow, or no, progress.

The CIA was also given the go-ahead to provide advice on Ukrainian strikes against Russia’s so-called shadow fleet in the Black Sea and Mediterranean, it is claimed.

The revelations come days after Mr Trump said agreement on a peace deal for Ukraine is “closer than ever before” following a meeting with Ukrainian President Volodymyr Zelensky in Florida on Sunday.

Moscow has said negotiations are “at a final stage”.