A British intelligence update said forces led by the private Russian military company Wagner Group had captured the villages of Optyine and Ivangrad south of the fiercely-contested town of Bakhmut, the first such advance in more than three months.

"There have been few, if any, other settlements seized by regular Russian or separatist forces since early July," said the daily update from London, which normally focuses on Ukrainian battlefield successes.

Ukraine launched a counteroffensive in late August against Russian forces occupying the country since the start of their invasion in February, pushing them out of the northeast and putting them under heavy pressure in the south.

Its main focus now is Kherson - one of four partially occupied Ukrainian provinces that Russia claims to have annexed in recent weeks, and arguably the most strategically important.

Russia's TASS news agency said evacuees from the Kherson region were expected to begin arriving in Russia on Friday, a day after a Russian-installed official advised all residents of the region to flee, especially those around Kherson city.

While some people in Russian-occupied areas of Ukraine have fled to Russia as Ukrainian forces advance, others have reported being forced towards Russia and others still have fled westward to Ukrainian-controlled parts of their country.

Reuters