The chief executive of Nordic and emerging markets telecoms group TeliaSonera resigned on Friday after an in-house investigation into its purchase of an Uzbekistan 3G licence harshly criticized the deal.
The report, which TeliaSonera had commissioned from a law firm, found no evidence of bribery or money laundering but said a lack of diligence by the company made it difficult to rule out somewhere along the line.
"If one does deals in a corrupt country, one simply has to be more careful than TeliaSonera was," lawyer Biorn Riese said in the 150-page report about a scandal that has dogged TeliaSonera since last year.
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"If one does not know the counterparty or how the counterparty has obtained the acquired assets, it seems difficult to ensure that corruption was not present at some stage," Riese said.
The upshot, he said, was that allegations of graft from Swedish prosecutors could not be dismissed.
Chief Executive Lars Nyberg said he was pleased that the report had offered no evidence to justify bribery and money laundering allegations levelled by Swedish prosecutors.
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But he acknowledged criticism that TeliaSonera had not dug deep enough to know who its Uzbek partner was and how he had come by the assets that TeliaSonera acquired.
"Even if this transaction was legal, we should not have gone ahead without learning more about the identity of our counterparty. This is something I regret," he said.
Nyberg's contract as chief executive had been due to end in December this year.
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The company appointed Chief Financial Officer Per-Arne Blomquist as acting CEO.
Swedish prosecutors launched an investigation in September into allegations that TeliaSonera knew that the company it paid 2.3 billion crowns ($361 million) for the licence was a front for top-level Uzbeks and that the deal involved money laundering and bribery.
That came after a Swedish investigative television program raised questions about how the deal was structured, for instance that it took place via a formerly unknown company based in Gibraltar. A Swedish court has already frozen assets belonging to the Gibraltar company, which is called Takilant.