Russian oligarch Alexander Lebedev is to sell his stake in state-controlled Aeroflot for $400m (£247m) in a bid to raise cash for other projects inaviation, agriculture and publishing, including the purchase of The Independent newspaper.

Aeroflot’s board has agreed to purchase Lebedev’s 25.8% share of Aeroflot, which is held by his National Reserve Corporation. Lebedev was the airline’s biggest private shareholder.

The deal could set the stage for Aeroflot to swap Lebedev’s stake for control of Rosavia, another state airline. The move would thereby remove the risk of a loss-making competition between two state airlines.

Lebedev has been seeking to sell his stake in Aeroflot for months, complaining that as a minority shareholder he wielded little influence over how the company was run. He has also been vocal in his criticism for how the company was run, in particular the spending millions of dollars on projects unrelated to Aeroflot’s core business.

Lebedev told the Guardian that he had reached a “gentleman’s agreement with the Russian government to invest the money in various social and development projects”.

These included low-cost housing, a building society for ordinary savers, and factories for his agricultural businesses that grow high-quality, low-cost potatoes.

Lebedev will also be using the funds to order and buy new Russian-made aircraft for his budget airline, Red Wings. According to the Russian financial newspaper Kommersant, he is also selling his 26% in Ilyushin Finance, an air leasing company, to the Russian state bank VEB for $175m.

The sale of Lebedev’s Aeroflot stake is likely to dispel lingering questions about his cash reserves and his ability to buy the Independent, following a torrid two financial years which has seen Russia’s oligarchs see their fortunes shrink dramatically.

Lebedev suggested today that his assets and investments are worth around $3bn.

Last year Lebedev, who also owns London’s Evening Standard, was briefly unable to pay salaries for journalists working on his Novaya Gazeta newspaper after his German-based airline, Blue Wings, was temporarily grounded. The airline has recently encountered fresh financial problems and was grounded again this month by the German regulator.