MegaFon, Russia's second-largest mobile phone operator, has received regulatory approval to list shares in London, edging closer to its long-awaited initial public offering that could raise $3 billion.

The company, in which Russia's richest man Alisher Usmanov took control in a complex deal in April, earlier this month asked the local markets regulator to allow it to list 123.38 million shares, or 19.9 percent of its shares outstanding.

FSFR, the watchdog, said on Thursday it granted MegaFon permission to list no more than 20 percent of shares outside Russia.

Analysts estimate that the IPO could raise at least $3 billion for Nordic co-owner TeliaSonera , which is expected to offer a 10.5 percent stake, and MegaFon itself, which would sell 9.4 percent of treasury shares.

(Reporting by Maria Kiselyova; editing by Megan Davies)