Lars Nyberg, the president and CEO of TeliaSonera, has decided to step down from his position at the operator, following a review of allegations surrounding the company's dealings in Uzbekistan six years ago.
The Sweden-based firm has appointed Per-Arne Blomquist as its acting president and CEO in Nyberg's place.
Serious allegations were made against TeliaSonera in the autumn of last year, in relation to the company's past investments in Uzbekistan.
It was claimed that the operator's investment in a 3G licence, frequencies and number blocks in Uzbekistan in 2007 might have involved corruption or money laundering.
Swedish law firm Mannheimer Swartling, which was assigned to make an outside assessment of the allegations, has now released its report into the claims.
In a statement concerning the report, the board of TeliaSonera noted that Mannheimer Swartling did not find any substance to allegations that the telecoms company took part in bribery or money laundering actions in Uzbekistan.
But it added: "Mannheimer Swartling also makes the natural observation that the suspicions of crime expressed by the Swedish Prosecution Authority cannot be dismissed by this investigation.
"The board's conclusion is that the investments were not carried out in a satisfactory manner."
Within its report, the law firm has criticised TeliaSonera for shortcomings in its investment processes, concluding that not enough effort was made to investigate either the local partner in Uzbekistan, or how the local partner could hold the rights which were later transferred.
It also pointed out that TeliaSonera's internal controls were not strong enough to ensure that the operator did not risk becoming involved in any unethical business activities.
On his departure, Nyberg said he was leaving partially due to a lack of board support surrounding his position.
"I am greatly relieved that Mannheimer Swartling has not found anything to support the allegations that TeliaSonera committed bribery or participated in money laundering," he said.
"This is something that I have been convinced of since these allegations emerged."
But he did admit regret at not learning more about the identity of the counter-party involved in the 2007 deal, stating that the firm should not have gone ahead with the transaction before it conducted an investigation into who it was dealing with.
Nyberg added that TeliaSonera's board was not prepared to express explicit support for him as CEO due to changes set to be implemented to its structure.
His final act last week was to oversee the release of the operator's 2012 financial figures, which saw profits rise by over eight percent.