Russia's military told Russian President Vladimir Putin on ​Friday that its forces had taken control of Kostiantynivka in eastern Ukraine, a key locality whose capture Moscow has ‌long sought in its advance through the Donetsk region.

Putin, shown in videos visiting a command post and receiving a report from top commanders, praised the city's capture as an important strategic achievement.

He also said Russian forces had to increase the scale of security zones in response to intensified Ukrainian long-range strikes, mainly ​against Russia's oil industry.

Ukraine made no comment on Russia's claim to have seized Kostiantynivka.

General Valery Gerasimov, chief of Russia's General ​Staff, announced the city's capture in a report on the conduct of the war, now in its ⁠fifth year.

Gerasimov said the southern group of forces was carrying out offensive operations to "liberate" all of the Donetsk region, part of the ​broader Donbas region over which Russia has vowed to secure control as a key aim of its war effort.

"The troops of the group have ​liberated the city of Kostiantynivka, one of the main defensive hubs of the enemy within the Sloviansk-Kramatorsk-Kostiantynivka fortified area", Gerasimov said.

Russia's military has for some time reported that its troops were in control of parts of Kostiantynivka, one of several cities seen as a network of key fortifications in Ukraine's defence of ​the region.

Putin described the city as having an important strategic significance.

"We all know that this city is a key transport and large ​industrial centre of Donbas," Putin said.

-Reuters