An expected winter-spring offensive by Russia is underway - but Russian forces are unlikely to "fail to achieve" their objectives, Ukraine's military spy chief has said.
The Institute for the Study of War's latest report cites a statement from the head of the defence ministry's intelligence directorate (GUR), General Kyrylo Budanov.
General Budanov said a Russian offensive in Ukraine is ongoing and that Moscow's troops are aiming to reach the Zherebets River, which lies in the Kharkiv-Luhansk border area of eastern Ukraine.
Russian forces are also pushing to reach the borders of the Donetsk and Luhansk regions, he said.
