”Throughout 2023, some 5.2 million barrels of refined petroleum products that had been produced from Russian crude oil were imported to the UK.
Most of the fuel imported - 4.6 million barrels - was jet fuel, which the group's researchers suggested was used in one in 20 UK flights…

the so-called loophole indirectly provided the Kremlin with more than £100m in tax revenues.”

https://www.bbc.com/news/business-68018660