Russia-Ukraine war could last for years, say western leaders

Nato secretary general says Kyiv will need long-term military support as Russia masses reserves outside Sievierodonetsk

• Russia-Ukraine war: latest updates

Western leaders have said the war in Ukraine could last for years and will require long-term military support as Russia brought forward reserve forces in an apparent attempt to capture the eastern city of Sievierodonetsk.

We must prepare for the fact that it could take years," Nato's secretary general, Jens Stoltenberg, said in an interview with the German newspaper Bild on Sunday. We must not let up in supporting Ukraine."