Russian sergeant Vadim Shishimarin waits for the start of a court hearing in Kyiv, Ukraine, on Monday. AP
"The court has found that (Vadim) Shishimarin is guilty and sentences him to life imprisonment," judge Sergiy Agafonov said.
Shishimarin, a Russian sergeant, admitted earlier in court to killing 62-year-old Oleksandr Shelipov in the first days of the Kremlin's offensive in north-east Ukraine.
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He was also found guilty of premeditated murder.
"The murder was committed with direct intent," judge Agafonov said.
"Shishimarin violated the laws and customs of war."
The Russian soldier told the court last week that he shot Shelipov under pressure from another soldier as they tried to retreat and escape back into Russia in a stolen car on February 28th, the fourth day of Moscow's invasion.
Russian sergeant Vadim Shishimarin stands in the defendant’s box on the last day of his trial in Kyiv. AFP
Shishimarin apologised and asked Shelipov's widow for forgiveness.
The youthful serviceman looked on from the glass defence box as the verdict was read out in Ukrainian. An interpreter translated for him into Russian.
Shishimarin's lawyer Viktor Ovsyannikov said he will appeal the verdict.
"This is the most severe sentence and any level-headed person would challenge it," Ovsyannikov, said following the court session, adding, that: "I will ask for the cancellation of the court's verdict".
He said that "you can feel societal pressure" on the decision of the court.
The Kremlin said before the sentencing Monday that while it was "concerned" over Shishimarin's fate, it was unable provide on-the-ground assistance because there is no Russian diplomatic presence in Ukraine.
"That doesn't mean we won't try through other channels. The fate of every Russian citizen is of paramount importance to us," Kremlin spokesman Dmitry Peskov told reporters.
The landmark ruling is expected to be followed by others, with Ukraine opening thousands of war crimes cases since Moscow's invasion.
The leaders vowed that Russian President Vladimir Putin and those responsible would be held to account for Monday's strike in the city of Kremenchuk, carried out during the shopping mall's busiest hours.
Ukraine’s president told the UN Security Council on Tuesday that the Russian military must be brought to justice immediately for war crimes, accusing invading troops of the worst atrocities since World War II.
Bodies with bound hands, close-range gunshot wounds and signs of torture lay scattered in a city on the outskirts of Kyiv after Russian soldiers withdrew from the area.
The Coromandel Express, which runs from Kolkata to Chennai, derailed and fell on the opposite track, with many people still trapped, the reports said.
Sheikh Mohammed added in a tweet on Twitter: "We found its executive director at the service counters, receiving customers, speeding up procedures, and contributing to clearing transactions. The secret shopper assured us that providing the service did not exceed five minutes."
The first lady arrived in Cairo from Amman, where she attended the wedding of Crown Prince Hussein. She is travelling to Morocco on Saturday before heading to Portugal, the final stop of her tour, on Monday.