The death in battle of at least one top Russian general in the invasion of Ukraine has shown that the military elite feel pressure to be personally present on the frontline, observers say.

With Ukraine claiming Tuesday a second Russian general had been killed -- an assertion not confirmed by Moscow -- the peril faced by commanders may be a sign they are putting themselves at risk to motivate troops after a sluggish initial advance.

The death in action of Major General Andrei Sukhovetsky has not been officially disclosed by the Russian defence ministry but several Russian sources have confirmed he was killed.

Sukhovetsky, deputy commander of Russia's 41st Combined Arms Army, "heroically" died in the Ukraine operation on February 28, announced the municipal administration in his native city of Novorossiisk in southern Russia.

Since joining the army in 1991, he had "devoted his life to serving the motherland" and from 2018-2019 had been deployed in Syria, it said.

Alexander Kots, the war correspondent for Russia's pro-Kremlin Komsomolskaya Pravda daily who is embedded with Russian troops in Ukraine, wrote on his Telegram channel that Sukhovetsky had been killed in fighting.

Ukrainian military intelligence said late Monday that Major General Vitaly Gerasimov, the deputy commander of the 41st army of Russia's central military district, had been killed outside Kharkiv.

It said that Gerasimov had taken part in the war in Chechnya and Russia's operation in Syria, and had also been decorated for his role in the 2014 annexation of the Ukrainian Black Sea peninsula of Crimea.

An audio recording also surfaced on social media purportedly of the moment the unit's commander in Russia was informed of Gerasimov's death by a subordinate in Ukraine. Its veracity could not be immediately verified.

His death has not been confirmed or denied by Russia, although pro-Kremlin Telegram channels on Tuesday insisted that Gerasimov was alive, well and carrying out his military duties.

There have also been unverified reports of at least two other Russian generals losing their lives at the front line.

Analysts say Moscow had hoped for a swifter advance through Ukraine and commanders may feel they need to take greater risks to speed progress
Analysts say Moscow had hoped for a swifter advance through Ukraine and commanders may feel they need to take greater risks to speed progress AFP / Dimitar DILKOFF

"What we know is that at least one deputy general of the 41st Army is known to have been killed, and possibly at least another," said a high-ranking French military source, who asked not to be named.

The source said that this could indicate that there was already a "guerrilla" resistance in Ukraine seeking to eliminate high-value targets but also "there may be a need for the leader to go ahead and expose himself (to danger), given the difficulties" of the campaign.

Military analysts say that Moscow had hoped for a swifter advance through Ukraine in the invasion that began on February 24 and commanders may feel they need to take greater risks in order to speed progress.

"The reported deaths of several Russian generals is a sign of the need -- or even an order - for the commanders of large units... to bypass a saturated chain of command and compensate for the lack of initiative of the units," said French military expert and retired colonel Michel Goya.

Morale of Russian troops is seen as a problem by some analysts, pointing to reports that the tens of thousands deployed for weeks on the border may have only found out they were being sent to war at the last moment.

Alexander Grinberg, analyst at the Jerusalem Institute for Security and Strategy, expressed astonishment that a figure of Sukhovetsky's seniority had been so close to the fighting.

"He was killed because no one was expecting war. They thought it would be a kind of police operation to put in place a pro-Moscow government," he said.

Moscow had "asked the generals to lead their troops and to take risks" to compensate for a "difficult morale situation", said Elie Tenenbaum, head of the Security Studies Center at the French Institute of International Relations.

"The Russian forces were only informed of the nature of the operation 24 hours in advance," he said, referring to "problems of troop morale and probably desertion, with vehicles abandoned in the open countryside".

But he warned against overestimating the strategic importance of the losses of generals. The functions of someone like Gerasimov could be assumed by lower-ranking figures.

"We must not be impressed by the ranks. But it hurts Russia all the same," he said.