Ukrainian forces have responded to Russian efforts to expel them from one part of Russian territory by launching a large number of attacks on another border area, using drones, artillery and troops.

Russian forces are preparing to launch a fresh military offensive in the coming weeks to maximize pressure on Ukraine and strengthen the Kremlin's negotiating position in ceasefire talks, Ukrainian government and military analysts said.

The move could give Russian President Vladimir Putin every reason to delay discussions about pausing the fighting in favor of seeking more land, the Ukrainian officials said.