Russian diplomat warns Ukraine against provoking third world war as ‘city falls’

A Ukrainian serviceman walks in a building near a frontline position in Kharkiv, Ukraine (Felipe Dana/AP)

Russia’s top diplomat has warned Ukraine against provoking a third world war and said the threat of a nuclear conflict “should not be underestimated” as his country unleashed attacks against rail and fuel installations far from the front lines of Moscow’s new eastern offensive.

Meanwhile, the UK’s Ministry of Defence (MoD) said on Tuesday that Russian forces have taken the Ukrainian city of Kreminna in the Luhansk region after days of street-to-street fighting.