German prosecutors have dropped an investigation into Russian oligarch Alisher Usmanov in return for a €10 million payment, the Munich II public prosecutor's office said on Tuesday, reported dpa. Prosecutors had been investigating suspected violations of Germany's foreign trade law and possible breaches of EU sanctions imposed after Russia's invasion of Ukraine in February 2022. Usmanov, considered a longtime ally of Russian President Vladimir Putin, was also placed on the EU sanctions list. Investigators said they suspected that between April and September 2022 Usmanov paid about €1.5 million via foreign-based companies for the surveillance of two properties near Lake Tegernsee in southern Germany. Usmanov, a multibillionaire according to Forbes magazine, was also suspected of failing to declare various valuables, including jewellery, paintings and wine, to the relevant authorities. Usmanov's defence denied any link between the oligarch and the companies involved, disputed ownership of the assets in question, and challenged the applicability of EU sanctions rules to the case. The proceedings were discontinued with the consent of the Munich II regional court and Usmanov, prosecutors said, citing the "particular circumstances of the individual case." They added that the case involved a number of legal questions that have not been clarified by the highest court, and that some of the alleged violations were considered to be more minor.