Russian forces are advancing from staging areas in Donbas towards Kramatorsk, which continues to be hit by rocket attacks, a British military update said on Thursday.
High levels of Russian air activity continue as it seeks to provide close air support to its offensive in eastern Ukraine, and to suppress and destroy Ukrainian air defence capabilities, the UK Ministry of Defence tweeted in a regular bulletin.
"Russia likely desires to demonstrate significant successes ahead of their annual 9th May Victory Day celebrations. This could affect how quickly and forcefully they attempt to conduct operations in the run-up to this date," the tweet added.
Reuters could not immediately verify the report.
(Reporting by Shivam Patel in Bengaluru; Editing by Kim Coghill)