Russian and Ukrainian delegations held talks Monday for the first time as Russia’s multifront assault on the country entered its fifth day, casualties mounted and tensions between Moscow and NATO escalated. They met near the border with Belarus as the United States and Western countries sought to tighten their financial stranglehold on Russia’s banking system and the number of refugees pouring into neighboring countries rose to more than half a million, according to a United Nations agency.

Meanwhile, three areas of Kharkiv, Ukraine’s second-largest city, came under heavy daylight shelling while civilians who had been under curfew ventured out to grocery stores and pharmacies. At least 11 people were reported killed and dozens hospitalized, according to the head of the regional government, in some of the heaviest shelling and street fighting since the invasion began. Both Kharkiv and Kyiv, the capital, remained in Ukrainian hands as Russia faced more resistance than it was expecting, according to the Pentagon.

The first talks between Russia and Ukraine over the invasion ended with agreement to continue talking in coming days. After almost five hours of talks in Belarus, the head of the Russian delegation, Kremlin aide Vladimir Medinsky, said further discussion would be held in coming days after both sides consulted with their presidents. Ukrainian presidential adviser Mykhailo Podolyak said “the parties identified a number of priority topics on which specific solutions were outlined.”

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