Russia said on Tuesday it was in control of the key city of Kupiansk in northeast Ukraine, where Ukrainian forces recently claimed to have retaken several areas.“The city of Kupiansk is under the control of the Russian Sixth Army,” Leonid Sharov, head of the Zapad military group, told state news agency TASS.For the latest updates on the Russia-Ukraine war, visit our dedicated page.Diplomatic efforts to resolve the conflict have continued this week in Berlin, where Ukraine’s President Volodymyr Zelenskyy hailed progress in talks with the US negotiators on Monday.European leaders have put forward plans for a multinational force to guarantee peace.Russia said it had captured Kupiansk in November but Ukraine later claimed it had retaken several areas of the city.Sharov said “small groups” of Ukrainian soldiers were trying daily to get into Kupiansk, a rail hub in the Kharkiv region.But he insisted: “All areas are under the control of Russian forces.”Zelenskyy said in a video published on