Guryev

Both Mr Guryev's daughter and Opus told us it happened before her father was sanctioned.

It was launched by the daughter of Russian billionaire Andrey Guryev to challenge the seizure of the Alfa Nero superyacht.

Before the yacht was seized in April, the US government said it belonged to Mr Guryev, whom it called a "known close associate" of Vladimir Putin.

It says it treats these assets as frozen because, while Mr Guryev is not a beneficiary of the trust, he is deemed to have "control" over it under UK sanctions law.

Since the sanctions were imposed, Guryev Snr and Jnr have both resigned their positions at PhosAgro, but the family remains major shareholders.