Russian President Vladimir Putin is planning new attacks to try and take more territory and strengthen his hand in ceasefire talks, Ukraine has claimed.
Ukrainian government and military analysts say three cities would be vulnerable as Russia attacks the over 600-mile frontline - Sumy, Kharkiv and Zaporizizhia.
Ukrainian president Volodymyr Zelensky also said: “They're dragging out the talks and trying to get the US stuck in endless and pointless discussions about fake 'conditions' just to buy time and then try to grab more land."
While limited ceasefire agreements in the Black Sea and over energy facilities were agreed last week, Russian forces continue to strike Ukraine.
Russian drones targeted a military hospital, shopping centre, apartment blocks and other targets in Kharkiv on Saturday.
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