South Africa added its voice to those calling for a summit between Ukraine and Russia.

Russian forces are slowly advancing in the embattled eastern region of Donetsk, grinding closer to Kyiv's key defensive line in costly meter-for-meter battles.

Moscow's defense ministry said on Telegram that its forces had captured the villages of Sredneye and Kleban-Byk.

The taking of Kleban-Byk would mark a further advance towards Kostiantynivka -- a key fortified town on the road to Kramatorsk, where a major Ukrainian logistics base is located.

On Friday, Russia said its troops had captured three villages in the Donetsk region it claimed to have annexed in September 2022.

On Saturday, Ukrainian military officials said its forces had stopped a Russian advance and recaptured the village of Zeleny Gai in the Donetsk region in a post to Telegram.

In July, Russia claimed the capture of the village, on the border with Dnipropetrovsk, adding that it was an important stronghold used by Ukraine to protect the area.

Ramaphosa backs summit

The latest Russian advances come as hopes dim for a summit between Russian and Ukrainian presidents -- a solution championed by US President Donald Trump as part of his efforts to end the conflict.

South African President Cyril Ramaphosa on Saturday added his voice to calls for a Russia-Ukraine summit during a telephone conversation with Ukrainian President Volodymyr Zelensky.

"President Ramaphosa stressed the urgency of holding bilateral and trilateral meetings between the leaders of Russia and Ukraine and the United States as key to signal a firm commitment to ending the war," said a statement from his office.

Ramaphosa, who currently chairs the G20, also spoke with French President Emmanuel Macron and Finnish President Alexander Stubb, the statement added. He will speak with other European leaders in the coming weeks.

Ramaphosa spoke on Monday with Vladimir Putin, whom he described in October at the BRICS summit as a "dear ally" and a "valued friend".

However, for the first time since Russia's attack on Ukraine, South Africa earlier this year backed a UN resolution declaring that Russia had launched a full-scale invasion of Ukraine.

Zelensky said he had told Ramaphosa he was ready for any kind of meeting with Putin.

"However, we see that Moscow is once again trying to drag everything out even further," he said on X.

He called on the Global South to send "relevant signals and [push] Russia toward peace".

On Friday, Russian Foreign Minister Sergei Lavrov said "no meeting" was planned as Trump's mediation efforts appeared to stall, while Zelensky accused Russia of trying to prolong the offensive.