Sign up now for FREE unlimited access to Reuters.com Register July 27 (Reuters) – Russian forces are undertaking a “massive redeployment” of troops in three southern regions of Ukraine in what appears to be a tactical shift by Moscow, a senior adviser to President Volodymyr Zelenskiy said on Wednesday. Russian forces seized Ukraine’s second-largest power plant, presidential adviser Oleksiy Arestovych said in an interview posted on YouTube. Russian-backed forces earlier announced their seizure of the Soviet-era coal-fired plant in Vuhlehirsk, eastern Ukraine. read more “They achieved a tiny tactical advantage – they captured Vuhlehirsk,” Arestovych said. Sign up now for FREE unlimited access to Reuters.com Register Arestovich said Russia appeared to be shifting from the offensive to a strategic defense, using tactical strikes in an attempt to weaken Ukraine’s offensive potential in the critical industrial region of eastern Donetsk. “(That would) put us in a position where we are not able to release all of our territory and call for talks,” he said. Ukraine has made it clear it intends to recapture the southern city of Kherson, which fell to Russia in the early days of the war. Oleksiy Danilov, secretary of Ukraine’s National Security and Defense Council, earlier tweeted that Russia was massing “the maximum number of troops” in the direction of Kherson, but gave no details. Arestovich said Russia is also sending troops to the Melitopol and Zaporizhia regions in the south. Ukraine has bombed a major bridge spanning the Dnipro River in Kherson, closing it to traffic. Russian officials had earlier said they would turn to bridges and ferries to get forces across the river. Sign up now for FREE unlimited access to Reuters.com Register Reporting by David Ljunggren and Ronald Popeski. Edited by Grant McCool Our Standards: The Thomson Reuters Trust Principles.