Russian oligarch Roman Abramovich secretly transferred hundreds of millions of dollars’ worth of assets — including superyachts and one of the world’s biggest private jets — to his children just days before he was placed under international sanctions, an analyst for the FBI has found.

Court documents filed last week in the US government’s effort to seize the billionaire’s pricey private planes revealed the convoluted machinations he has used to shield his vast wealth, the Sunday Times of London revealed.

In an affidavit filed Monday to the Southern District of New York, FBI Special Agent Alan Fowler wrote that Abramovich, a longtime ally of Vladimir Putin, used a series of shell companies to purchase the two aircraft — a bespoke Gulfstream G650ERa worth about $60 million and a customized Boeing 787-8 Dreamliner valued at $350 million, one of the most expensive private jets in the world.

In February 2022 — just days before Putin’s February 24 invasion of Ukraine triggered punishing sanctions against the Russian president’s oligarch cronies — Abramovich made some or all of his seven children the beneficiaries of the Cyprus-based Europa Settlement Trust, the document alleges.

The Europa Trust controls the shell companies that, on paper, own Abramovich’s jets, several yachts, a helicopter, and other assets, Fowler found.

Abramovich, who made his fortune through Russian energy firms in the early years of Putin’s “KGB capitalism,” and found fame as the flashy owner of London’s Chelsea Football Club, has four daughters and three sons between the ages of 8 and 30 — all of whom hold dual citizenship in Russia and either Britain or the US, NYPOST reports.