Kiev, Sep 4 : Ukrainian Defence Minister Oleksii Reznikov on Monday said he has submitted a letter of resignation to parliament chairman Ruslan Stefanchuk after his dismissal by President Volodymyr Zelensky. "It was an honor to serve the Ukrainian people and work for the Ukrainian army for the last 22 months, the toughest period of Ukraine's modern history," Reznikov said on the social media X, formerly known as Twitter. In the letter, the 57-year-old, who was appointed as Defence Minister in November 2021, said that all the key tasks set for his mandate have been accomplished, reports Xinhua news agency. Rustem Umerov, who runs Ukraine's State Property Fund, has been nominated by Zelensky as Reznikov's successor. In his nightly address to the nation, Zelensky on Sunday said: "This week, Parliament will be asked to make a personnel decision... I have decided to replace the Minister of Defence of Ukraine. Oleksii Reznikov has gone through more than 550 days of full-scale war. "The Verkhovna Rada (legislature) of Ukraine knows this person well, and Umerov does not need any additional introductions... I expect Parliament to support this candidate." Reznikov's removal comes in the wake of a number of corruption scandals involving Ukraine's Ministry of Defence, reports CNN. While he has not been implicated in any of them, the scandals have still been seen to damage him by association. Earlier this year, Reznikov's deputy Vyacheslav Shapovalov had resigned in the wake of the scandals. At the time, Reznikov said the stress he had endured this year "is hard to measure precisely", adding that his "conscience is absolutely clear". Meanwhile, Umerov, who represented Ukraine in peace talks at the beginning of Russia's full-scale invasion, allegedly suffered symptoms of suspected poisoning during peace negotiations in March 2022 alongside Russian billionaire Roman Abramovich -- who was also part of the negotiating party, reports the BBC. In a social media statement, he later denied the reports, urging people not to trust "unverified information". Speaking to the BBC at the time, he said it took courage to find solutions but he was determined "to find (a) political and diplomatic resolution to this brutal invasion". The Ukrainian President made cracking down on internal scandals a central issue in his campaign for office. On Saturday, one of Ukraine's most powerful oligarchs and a key Zelensky supporter, Ihor Kolomoisky, was arrested as part of a fraud investigation. /IANS