Russia is massing tens of thousands of troops in Kursk, where it is attempting to regain control of the territory lost to Ukrainian forces following Kyiv's incursion into the Russian region this summer, Ukraine's top military commander said on November 11.
"Following the orders of their military leadership, they are trying to displace our troops and advance deep into the territory we control," Colonel General Oleksandr Syrskiy wrote on social media, adding, "Were it not for the resilience of our soldiers, these tens of thousands of enemies from the best Russian units would have stormed our positions."
Ukrainian forces in August launched an unexpected incursion into Kursk, which borders Ukraine, capturing several settlements and strengthening their positions in the first such deployment into Russian territory since Moscow launched its full-scale invasion of Ukraine in February 2022.
According to Ukraine's military, its forces have seized control of some 1,000 square kilometers of Russian territory since August, with Moscow acknowledging that 28 settlements were under Ukrainian control.
Syrskiy on November 9 confirmed reports that thousands of North Korean soldiers were massing alongside Russian forces in Kursk likely in preparation for a counteroffensive.
Separately, President Volodymyr Zelenskiy said in a post on Telegram on November 11 that Ukrainian forces in Kursk "continue to hold back the almost 50,000-strong enemy group outside of Ukraine."
SEE ALSO: 'They're Totally Not Ready': Ex-Soldier Reveals Why North Korean Troops Will Struggle Against Ukraine"We have numerous data on the preparation of North Korean soldiers to participate in combat on the side of Russian troops," Syrskiy wrote on Facebook following a telephone conversation with General Christopher Cavoli, who heads the U.S. European Command. He said he told Cavoli that the situation "remains challenging and shows signs of escalation."
On the same day, the EU's foreign policy chief Josep Borrell traveled to Kyiv in what is the first visit by a senior Western official to Ukraine since Donald Trump won the U.S. presidential election last week.
Trump and his allies have suggested that Ukraine may have to cede territory to Russia to secure a peace deal and end the war.
"Certainly it would not be a victory for the American leadership if Ukraine crumbles down and Putin wins the war," Borrell told the AFP news agency on his last visit to Ukraine before leaving office. His trip appeared to be aimed at allaying concerns in Kyiv about whether it still has the EU's backing irrespective of the outcome of the U.S. election.
Ukraine's outmanned and outgunned forces in the east have been facing a grinding Russian offensive that has been making incremental progress despite huge losses on Moscow's side.
According to an estimate by Britain's Chief of the Defense Staff Tony Radakin, an average of some 1,500 Russian soldiers were killed or injured per day in October -- Russia's worst month for casualties since the beginning of the invasion.
WATCH: At least five people were killed in a Russian strike on a residential building in the southern city of Mikolayiv, while seven people, including two children, were hurt in a strike in Kriviy Rih.
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Russian Strikes On Ukraine's Mykolayiv, Kryviy Rih Leave At Least 5 Dead (Video)
Meanwhile, Russia was continuing to pound Ukrainian cities and energy infrastructure at the onset of the cold season -- a third winter of war for Ukraine's civilian population that in previous years faced energy shortages.
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In the southern city of Mikolayiv, at least five people were killed In a Russian strike on a residential building early on November 11, regional Governor Vitaliy Kim said. The mayor of the city, Oleksandr Syenkevych, said Russian strikes damaged residential buildings in several areas of the city.
In another southern city, Zaporizhzhya, one person was killed and 21 others, including a 4-year-old boy and four teenagers, were wounded in three Russian strikes, regional Governor Ivan Fedorov reported, adding that a residential building and a school dormitory were damaged in the attack.
Blasts were also heard in Kyiv, and areas of the Ukrainian capital were left without power early on November 11. Ukraine's air force declared an air-raid alert for the whole territory of Ukraine early on November 11.
The air force said its air defenses shot down 39 out of 74 drones launched by Russia at nine regions -- Kyiv, Zhytomyr, Poltava, Sumy, Cherkasy, Zaporizhzhya, Chernihiv, Dnipropetrovsk, and Mykolayiv.
It said that 30 Russian drones were lost after being jammed by Ukrainian electronic-warfare systems.