Medvedev, who launched a drive to wean Russia’s economy off oil and gas, will on Monday chair a meeting of the Kremlin’s commission on modernisation.

Prokhorov, whose fortune is estimated by Forbes at $18 billion and is a long-serving member of the commission, did not receive an invitation to Monday’s meeting, said Kommersant, citing a Prokhorov aide and other sources.

Prokhorov’s spokeswoman Olga Stukalova declined comment on Saturday.

The snub, which an unidentified Prokhorov aide called a “public flogging,” comes after the free-wheeling billionaire last week quit the post of leader of the Pravoye Delo (A Right Cause) Kremlin-backed party and accused Medvedev’s top strategist Vladislav Surkov of stifling debate.

“There is a puppeteer who has long ago privatised the political system, puts pressure on media and misinforms the country’s leadership,” the owner of the NBA’s New Jersey Nets basketball team told a party meeting, vowing to do everything he can to have Surkov fired.

Surkov is considered one of the most influential Kremlin officials and is credited with coining the term “sovereign democracy” to describe Russia’s political system.

Such a lacerating critique of the Kremlin was startling in a country where top businesspeople and parties have for years toed the Kremlin line and Russian state-controlled television and three main news agencies excised all criticism concerning the Kremlin official.

A day after Prokhorov’s unprecedented attack the billionaire and his close political associate became the target of a muckraking documentary shown on primetime state-controlled television.

Prokhorov’s interests range from mining and metals to eco-friendly cars, and include stakes in Russia’s biggest gold company Polyus Gold and the world’s biggest aluminum producer United Company Rusal.

Kommersant, citing a high-ranking member of the Kremlin’s modernisation commission, said Prokhorov’s absence would only be logical, adding “it is hard to imagine that he’ll be sitting there next to Surkov.”

The newspaper said a formal announcement about staffing changes in the commission could be made Sunday.

As he announced his resignation last week, Prokhorov also publicly requested a meeting with Medvedev and Prime Minister Vladimir Putin. Spokespeople for Russia’s ruling duo indicated the two leaders had no plans to meet with the tycoon.