Michel Platini
Michel Platini, president of the Union of European Football Associations, looks on before the preliminary draw for the 2018 FIFA World Cup at Konstantin Palace in St. Petersburg, Russia, July 25, 2015. He is a candidate to become the next FIFA president. Reuters

Kevin Lamour, a top European soccer official and close adviser to FIFA presidential candidate Michel Platini, stepped down from his position Thursday at the Union of European Football Associations, a report said. Lamour's apparent resignation came amid Platini's involvement in a Swiss criminal probe of outgoing FIFA President Sepp Blatter.

Platini, UEFA's longtime president, counted Lamour among his closest associates. Pedro Pinto, a UEFA spokesman, described Lamour's resignation as an indefinite leave of absence, Bloomberg Business reported. Lamour purportedly told co-workers "not to judge him over the timing of his departure," the report said. Lamour has yet to publicly address the situation.

Platini, 60, was considered a front-runner to succeed Blatter, who announced his resignation from FIFA, effective February 2016, days after the unprecedented arrests of nine current and former FIFA employees on corruption charges last May. Though presenting himself as a candidate for internal reform, Platini's bid to become FIFA's next president was damaged last week after Swiss authorities announced a criminal probe into Blatter's activities on suspicion of "criminal mismanagement."

Swiss authorities said Platini, who does not face criminal charges, was asked about a $2 million payment Blatter gave him in 2011. Platini has denied any wrongdoing and said the money was a legitimate payment for services rendered nearly a decade prior, when he was an adviser to Blatter. Platini intends to continue his presidential bid, despite his association with the Blatter probe and a formal FIFA investigation into his activities.

"There is no doubt about my integrity. I have done nothing wrong. That is why I have made myself fully available to cooperate with the relevant bodies and authorities to clarify whatever may be necessary," Platini told Agence France-Presse this week. "I was employed by FIFA as a special adviser to president Sepp Blatter, working on various matters related to football, such as the international football calendar. It was a full-time job."