Russian oil giant Rosneft has confirmed its intention to float shares in the company on both the Moscow and London stock markets.
Rosneft's launch on the London stock market concerns some investors
It has not said what percentage of the firm will feature in the initial public offering (IPO), but Russians will be able to buy stock from 29 June.
Reports suggest state-run Rosneft hopes to raise $10bn (£5.4bn) from the float, expected to take place in mid-July.
Analysts said the money probably will be used to pay back a large loan.
Rosneft's core shareholder is state-owned Rosneftegaz.
Rosneftegaz borrowed $7.5bn last year to buy additional shares in Russian gas monopoly Gazprom, thereby increasing state control over the gas giant.
Analysts say the Kremlin plans to use proceeds from the Rosneft IPO to pay off this loan before the end of this year.
Rosneft's flotation has attracted controversy, not least in London where there are concerns from some quarters over the standard of Russia's corporate governance.
The company is one of the world's largest oil firms and Rosneft made a net profit of $802m in the first quarter of 2006.
That was an 11% increase on the $724m figure achieved during the same time last year.