A Russian oligarch sanctioned for being a member of Vladimir Putin’s inner circle was a “major benefactor” for a Kent private school.

Documents show the King’s School in Canterbury – which charges almost £41,000 a year in boarding fees – accepted a donation from fertiliser manufacturer Uralchem JSC.

The firm was – until March 2022 – run by billionaire Dmitry Mazepin, who was sanctioned four months ago by the UK for his ties to Russia’s dictator.

The 64-year-old’s son, former F1 driver Nikita, was also slapped with restrictions for benefitting from his fortune, which was estimated to be worth $1.3bn by Forbes in 2015.

And in the school's 2019 annual review, it named Uralchem JSC as one of its five largest donors, alongside former Saga boss Sir Roger De Haan and the wealthy Swire family.

The school leaflet listed the firm as a “major benefactor” in a section “acknowledging the generosity of many of those who kindly supported King’s [between] September 1, 2011, to August 31, 2018”.

But when asked about the school’s association with the company, headmaster Peter Roberts said: “We do not make comments in such circumstances.

“However, please be reassured that we always apply full due diligence in these important matters and carefully comply with all regulatory guidance.”

The papers do not explain Uralchem’s relationship with King’s, nor do they indicate how much the company has donated to the school, which is thought to be Britain’s oldest.

Belarus-born Mazepin was first sanctioned by the European Union at the beginning of March, following Russia’s invasion of Ukraine the month before.

EU chiefs listed the businessman’s Uralchem Group as a “substantial source of revenue” to his country’s brutal regime.

They added: “On February 24, Dmitry Mazepin, along with 36 businesspeople, met with President Putin and other members of the Russian government to discuss the impact of the course of action [in Ukraine] in the wake of western sanctions.

"We always apply full due diligence in these important matters and carefully comply with all regulatory guidance..."

“The fact he was invited to the meeting shows he is a member of Putin’s closest circle and is supporting or implementing actions or policies which undermine or threaten the territorial integrity, sovereignty and independence of Ukraine, as well as its stability and security.”

The UK also sanctioned Mazepin, as well as his son, shortly afterwards, noting he “is or has been involved in obtaining a benefit from or supporting the Russian government” through his roles with Uralchem Group and its JSC namesake.

A month later, Nikita Mazepin was dumped by his F1 team Haas.

King's School - which boasts Christopher Marlowe, Michael Morpurgo and William Harvey as notable former pupils - was established in 597AD.