The ex-wife of Russia’s richest man, Vladimir Potanin, is demanding half of his $US15 billion ($AU20 billion) fortune.

After their divorce last year following 30 years of marriage, Natalia Potanina was offered a monthly allowance of $US250,000 and properties in New York, Moscow and London — but she scoffed at the paltry sum.

Natalia launched an international fight to get a hold of his astronomical wealth, which she claims is held in offshore companies, CNNreported.

Her ex-hubby, a former Russian deputy prime minister, runs several companies and owns 30 per cent of nickel behemoth Norilsk Nickel, which is valued at more than $US30 billion, the network reported.

Natalia claims she is entitled to half his fortune because Russian law mandates that wealth acquired during marriage be divided equally.

She said she’d give her shares of Norilsk to the state.

“I want to avoid corporate conflicts. I want such a big strategic object to be under the state control,” she told CNN

The $AU10 billion payout would make her twice as rich as Aussie billionaires Frank Lowy and James Packer, according to Forbes’ 2015 Australia’s 50 Richest People list.

Natalia, who has three children with Vladimir, said she has been hurt by the split.

“I feel offended after living together for 30 years,” she told CNN.

“I loved him so much — it was a big personal drama to me.”

A court hearing is scheduled for July 1.

This story originally appeared in The New York Post.