In total, Ukrainian forces recaptured about 500 sq km of territory in the south of the country over the past two weeks, Reuters is reporting.

Natalia Humeniuk, a spokesperson for Ukraine’s southern military command, said on Monday that Ukrainian forces had retaken five settlements in the Kherson region.

Ukrainian forces outnumbered Russians by eight to one in last week's counter-attack in the Kharkiv region, Russia's top occupation official there says.

Vitaly Ganchev told Russian TV that Ukraine's army had taken villages in the north and broken through to the Russian border.

Ukraine says it has regained control over 3,000 sq km (1,158 sq miles) of territory in a potential breakthrough in the six-month war.

The BBC cannot verify these figures.

The Ukrainian army says it took back 20 villages in the past 24 hours alone, in its continued counter-offensive in the north-east of the country.

It also said its forces have taken control of around 500 sq km in the southern Kherson region of the country.

UK defence officials say the Ukrainian army's successes will have "significant implications" for Russia's overall operational design.

A Kremlin spokesperson was however undeterred, saying operations in Ukraine would continue "until all the tasks that were initially set" had been fulfilled.

Russia said its forces were carrying out strikes in those areas that Ukraine had retaken recently.

This included targets in Izyum and Kupiansk which were taken by Ukraine on Saturday. Russia confirmed its forces' retreat from both towns, which it said would allow them to "regroup".

Russia has been accused of targeting civilian infrastructure in revenge for setbacks on the battlefield.

A wave of missile strikes on Sunday caused power cuts across the region.