Ukraine's commander-in-chief has reportedly rejected a request from Volodymyr Zelensky to step down amid what appears to be a long-running dispute between the two men.
Media reports stated that the Ukrainian president sought to transfer Valery Zalozny to a new position.
But the Supreme Commander of the Ukrainian Armed Forces refused.
Zelensky's office denied reports that the army chief had resigned or been fired, but rumors that he could be dismissed in the coming days persist.
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The Ukrainian president is already preparing for a shake-up, in what would be the most significant change in military leadership since the Russian invasion nearly two years ago, the Financial Times reported.
This follows the lower-than-expected results of last year's Ukrainian counteroffensive, rumors of an upcoming Russian spring offensive, and issues of obtaining aid from Kiev's allies in Europe and America.
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The Kremlin said it was monitoring the situation around Zalozhny. Kremlin spokesman Dmitry Peskov said: “There are still many questions.
“[But] “One thing remains clear: the Kiev regime has a lot of problems, and things are not going well there.”
The two men were at loggerheads at the end of last year, when Zalozny said the war was heading toward a new phase of constant and attritional fighting, drawing comparisons with World War I, and saying a level of technology had been reached that “puts us in a stalemate.”
President Zelensky denied that the conflict had reached a dead end.
“Today, time has passed and people are tired. But the situation is not at a dead end,” he said.
Mr. Zalozny later commented that the war was not a stalemate.