The Russian military withdrew from the crucial eastern Ukrainian city of Lyman on Saturday, a day after President Vladimir V. Putin unlawfully annexed four territories of Ukraine.

Influential friends of Putin swiftly launched fervent criticism of the Russians' withdrawal, blaming military leaders for the recent setbacks and branding them as inept.

The United States and the United Nations strongly criticized the annexation as illegal. This drove the Biden administration to impose swift fresh sanctions on Russia.

The seizure of Lyman puts further strain on the Kremlin, which has been dealing with a domestic backlash over the recruitment of tens of thousands of men to join the Russian-Ukraine war, according to The New York Times.

Weeks were spent fighting for Lyman, but the Russians' unexpected retreat was due to their worry of being surrounded and abandoned.

A few hours later, the Russian Ministry of Defense declared that Russian forces were leaving the city.

Fighting Still On-Going Near Russian-Annexed Territories

Although the Ukrainian flag was raised in the city, Ukrainian President Volodymyr Zelenskyy claimed in a televised address that "fighting" is still happening in the area. Additionally, he said Ukrainian forces had seized Torske, a settlement on the major route east of Lyman.

According to a tweet from Ukraine's defense ministry, "almost all" of the Russian soldiers in Lyman had either been killed or arrested.

Russia officially seized Donetsk and neighboring Luhansk on Friday; Lyman is located in Donetsk, some 100 miles (160 kilometers) southeast of Kharkiv, Ukraine's second-largest city.

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Ukraine's eastern army spokesperson, Serhii Cherevatyi, claimed that the Russian brigade in the vicinity of Lyman is "surrounded."

Lyman has served as an essential transportation and supply center for Russia's activities in the northern Donetsk area. Capturing it marks the largest battlefield victory for the Ukrainian forces since the recapturing of the Kharkiv region to the north last month.

Kadyrov Suggests Use of Strategic Nuclear Weapons in Ukraine

Following a recent loss on the battlefield, Ramzan Kadyrov, the leader of Russia's Chechen province, warned on Saturday that Moscow should consider unleashing a low-yield nuclear weapon in Ukraine, per Reuters.

On Telegram, Putin's ally blasted Russian top military leaders and suggested "more drastic measures" should be employed, including "martial law" and unleashing of "low-yield nuclear weapons."

The day following President Putin's proclamation of the annexation of four Ukrainian areas, Kadyrov called Colonel-General Alexander Lapin, commander of the Russian soldiers battling at Lyman, a "mediocrity" and proposed he be reduced to the rank of private and deprived of his decorations.

Kadyrov said he had discussed a Lyman loss with Russia's general staff two weeks earlier, but Valery Gerasimov had rejected the notion.

The Biden administration on Friday reiterated its warning that Russia might be considering using nuclear armament but that there are no signs of an "imminent use" of such weaponry, as reported by ABC News.

National Security Advisor Jake Sullivan said that President Biden and his administration underscore that Putin's "nuclear saber-rattling" and "all of the loose talk" indicates danger, and the US has been "equally clear about what the consequences would be."

Sullivan said the risk of Russia's nuclear weapons usage "has been there from the start" of the war in Ukraine. However, he did not quantify the threat.

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