Swiss bank account data to be disclosed to island’s chief legal adviser who is looking at source of former Chelsea FC owner’s Sibneft billions

The former Chelsea football club owner Roman Abramovich is the subject of a criminal investigation by the Jersey authorities over allegations of corruption and money laundering in connection with the original source of his billions, according to court documents.

The information has emerged from the federal criminal court in Switzerland, where judges ordered the release of documents, relating to multiple Swiss bank accounts, that had been requested by the Jersey attorney general.

The Channel island’s authorities have been battling companies suspected of being connected to the Russian oligarch in the Swiss courts as part of their investigation into his vast wealth. The crown dependency – through which Abramovich pumped some of his cash into the west – froze more than $7bn (£5.2bn) of assets suspected of being linked to him soon after Russia’s invasion of Ukraine in 2022.

According to the Swiss rulings, Jersey investigators are looking into the very origins of the oligarch’s wealth, acquired during the chaotic, freewheeling rise of capitalism in Russia in the 1990s and 2000s.