IN BRIEF: Ukraine-Russia conflict | What you need to know right now

The war in Ukraine could last for years and Kyiv’s allies should keep up their support, NATO Secretary-General Jens Stoltenberg said, while fierce fighting continued in the east of the country.

Ukraine’s armed forces said Russian forces were carrying out shelling in the areas of Lysychansk, Borivske, Bila Hora, and Ustynivka. In its daily update, the military said fighting continued for full control of Sievierodonetsk.

Britain’s defence ministry said there had been little change in the front line on the axes to the north, east, and south of the Sievierodonetsk pocket.

Analysts at the Washington-based Institute for the Study of War think tank wrote that “Russian forces will likely be able to seize Sievierodonetsk in the coming weeks but at the cost of concentrating most of their available forces in this small area”.

A fuel storage depot in the eastern Ukrainian town of Novomoskovsk exploded, killing one and injuring two, after earlier being hit with three Russian missiles, the head of the regional administration said in an online message. Reuters could not independently verify battlefield reports.

PRISONERS, DIPLOMACY

Two top commanders of fighters who defended the Azovstal steel plant in the southeastern port of Mariupol have been transferred to Russia for investigation, Russia’s state news agency TASS reported.

Ukraine’s defence intelligence directorate said on Saturday five Ukrainian civilians had been returned in a swap for five Russian prisoners. It did not say whether the Russians were combatants.

British Prime Minister Boris Johnson warned of a need to prepare for a long war, which meant ensuring “Ukraine receives weapons, equipment, ammunition and training more rapidly than the invader”.