Ukraine has acknowledged for the first time that Russia's army has entered the Dnipropetrovsk region, a central administrative area previously spared from intense fighting.
"Yes, they have entered, and fighting is ongoing as of now," Viktor Tregubov, spokesperson for the Dnipro Operational Strategic Group of Forces, told AFP.
Moscow first said its forces had advanced into the region - which it has not made a formal territorial claim over - in July. It has since claimed to have captured some settlements there.
In a separate statement, Ukraine's General Staff rejected Moscow's claims to have fully captured the villages of Zaporizke and Novogeorgiivka.
But battlefield monitor DeepState, which has close ties to Ukraine's military, said today that Russia had "occupied" them.
The Russian army "is now consolidating its positions, and is accumulating infantry for a further advance," it added in a social media post.
Russian forces are slowly but steadily gaining ground in costly battles for largely devastated areas in eastern and southern Ukraine, normally with few inhabitants or intact buildings left.
Dnipropetrovsk is not one of the five Ukrainian regions - Donetsk, Kherson, Lugansk, Zaporizhzhia and Crimea - that Moscow has publicly claimed as Russian territory.
The concession from Ukraine that it has lost ground for the first time in the region comes as momentum towards a possible peace deal has stalled.
After US President Donald Trump met both Vladimir Putin and Volodymyr Zelensky, raising hopes for a breakthrough, Moscow has since ruled out any immediate meeting between the Russian and Ukrainian leaders.
Mr Putin is demanding Ukraine withdraw from some territory it still controls as a precondition to halting his invasion - demands rejected as a non-starter in Kyiv.

Turkey, Gulf states or European nations could host talks with Putin - Zelensky
Meanwhile, Mr Zelensky said today that Turkey, the Gulf States or European countries could host any talks he may hold with Mr Putin.
Mr Zelensky is pushing for direct talks with Mr Putin to help end Russia's war in Ukraine but Russian Foreign Minister Sergei Lavrov said no agenda had been prepared for such a meeting.
"Now, this week there will be contacts with Turkey, contacts with the Gulf States and with European states which could host talks with the Russians," Mr Zelensky said in his nightly video address.
"From our side, things will be prepared to the maximum in order to end the war."
Mr Zelensky spoke as his chief of staff, Andriy Yermak, said he and Ukraine's national security council chief were in Qatar to meet that country's defence minister.
In his comments, Mr Zelensky also said that moving ahead with talks depended on coordination with Ukraine's partners, primarily the United States, in ensuring that sufficient pressure was exerted on Russia. This, he said, had been discussed yesterday in Kyiv with US envoy Keith Kellogg.
"Everything further depends strictly on the will of world leaders, most importantly the United States of America, to put pressure on Russia," Mr Zelensky said.
"Russia is only giving signals that it is going to continue to avoid real negotiations. This can only be changed by strong sanctions, strong tariffs - real pressure," he said.
Ukrainian men aged 18-22 now allowed to cross the border freely, PM says
Mr Zelensky's comments come as Prime Minister Yulia Svyrydenko said Ukrainian men aged 18 to 22 are now allowed to cross the border freely in either direction under martial law.
Previous regulations introduced after Russia's February 2022 invasion barred men aged 18-60 from leaving the country.
"This applies to all citizens in this age group. The decision also concerns citizens who, for various reasons, are located outside Ukraine," Ms Svyrydenko wrote on Telegram, referring to a government decree.
"We want Ukrainians to maintain a maximum of links with Ukraine. The changes take effect the day after official publication."
Accreditation: Reuters/AFP