Russian mercenary boss Yevgeny Prigozhin told Defence Minister Sergei Shoigu in a letter published on Monday that the Ukrainian army was planning an imminent offensive aimed at cutting off his Wagner forces from the main body of Russian troops in eastern Ukraine.
In the letter published by his press service, Prigozhin said the "large-scale attack" was planned for late March or the start of April.
"I ask you to take all necessary measures to prevent the Wagner private military company being cut off from the main forces of the Russian army, which will lead to negative consequences for the special military operation," he said, employing the term that Moscow uses for its war in Ukraine.
It was the first time Prigozhin has published such correspondence with the defence minister, whom he has frequently criticised over the conduct of the war.
The unusual move appeared to have two possible aims: to wrongfoot Ukraine commanders and to seek to pin blame on Shoigu, not Prigozhin, if the purported Ukrainian manoeuvre proved successful.
Prigozhin said he was providing details of the Ukrainian plan and of his own proposal to counter it in an attachment to the letter, which he did not make public. He did not say how he knew of Ukraine's intentions.
He said Wagner forces currently controlled 70% of the Ukrainian city of Bakhmut, which they have been trying to capture since last summer in the longest and bloodiest battle of the war.
In separate comments published by a regional news channel on Telegram, Prigozhin said there was a "high probability" that the southern Russian city of Belgorod would be one of the targets of the coming Ukrainian offensive.
He gave no evidence to support his assertion that Ukraine might launch a full-scale attack on a Russian city.
Russia has frequently accused Ukraine of mounting isolated cross-border strikes by drones and other means. Ukraine has not claimed responsibility for such incidents but has described them as "karma" for Russia's invasion.
(Reporting by Mark TrevelyanEditing by Gareth Jones)
