The chief executive of TeliaSonera resigned Friday after an independent review...found it had failed to conduct a proper background check on a partner Uzbek firm [Takilant] believed to be connected with the family of the country's autocratic ruler...In 2007, TeliaSonera and Takilant signed a...$350 million...deal that included the purchase of a 3G operating license in the Uzbekistan mobile phone market..."Even if this transaction was legal, we should not have gone ahead without learning more about the identity of the counterparty," TeliaSonera CEO Lars Nyberg said in a statement. "This is something I regret."...[He] said there would be significant changes to TeliaSonera's board in light of the review.