British official predicts attrition war next in Ukraine

British officials say the next phase of the war in Ukraine is likely to be "an attritional conflict" that could last several months.

A senior UK national security official briefed the Cabinet on Tuesday, as Russia ratcheted up its battle for control of the eastern Donbas region.

Prime Minister Boris Johnson's spokesman said the official told ministers that Russia's greater number of troops was "unlikely to be decisive on its own" against fierce Ukrainian resistance.

The official told Cabinet that there are signs Russia has not learned the lessons from previous setbacks in northern Ukraine, with evidence of troops being committed to the fight in a "piecemeal fashion" and some soldiers and units refusing to fight.

Johnson's spokesman, Max Blain, said the prime minister had told Cabinet that Ukraine's position remained "perilous," with Russian President Vladimir Putin "angered by defeats but determined to claim some sort of victory regardless of the human cost."