Russian forces have captured 1,700 square kilometers (656 square miles) of Ukrainian territory this year and are advancing on Ukraine’s so-called fortress belt in Donbas, Moscow’s top general said during an inspection of his troops.

Moscow has, since its 2022 invasion, ​been seeking to take the whole of the Donbas area ​in ⁠eastern Ukraine, where Kyiv's forces have been pushed back toward a line of cities in grinding fighting.

Kyiv has also reported some gains in the deadliest war in Europe since World War II. Top Ukrainian commander Oleksandr Syrskyi said in mid-April that Kyiv's forces had regained control of nearly 50 square kilometers of its territory in March.

"Since the beginning of this year, a total of 80 settlements and more than 1,700 square kilometers of territory have come under our control," Valery Gerasimov, Chief of the General Staff of the Russian Armed Forces, said in footage released by the Defense ⁠Ministry ⁠Tuesday.

Reuters was unable to verify the battlefield accounts and a spokesperson for Ukraine's General Staff said he would not comment on the claim. Pro-Ukrainian maps indicate Russia has taken around 600 square kilometers this year.

Gerasimov said Russia's Southern Grouping of forces was attacking the Donetsk fortress belt comprising the cities of Sloviansk, Kramatorsk and Kostiantynivka, and that Russian forces were about 7 to 12 kilometers (4.3 to 7.5 miles) from Sloviansk and Kramatorsk.

Russian units were already fighting in parts of Kostiantynivka, ⁠he said. In addition, Gerasimov said, Russian forces were advancing in Sumy in the north and Kharkiv in the northeast to create what he called "a security zone."

Kyiv's military said Tuesday that its ​forces had stopped two Russian attempts to advance around villages near Sloviansk over the past ​24 hours and that Moscow had carried out 19 attacks near Kostiantynivka and eight nearby villages.

It also said Russian forces had made five attempts ⁠to break Ukrainian ‌defences around ‌several settlements near the Russian border in the Kharkiv region.

According ⁠to Russian estimates, Russia controls about 90% ‌of Donbas, about 75% of the Zaporizhzhia and Kherson regions, and slivers of the Kharkiv, Sumy, Mykolaiv and ​Dnipropetrovsk regions in Ukraine.

Russia also controls ⁠Crimea, which it annexed in 2014 after earlier fighting. The ⁠Black Sea peninsula is internationally recognised as part of Ukraine by most countries.

Pro-Ukrainian maps ⁠show Russia controls ​116,793 square kilometers, or 19.35%, of Ukraine, but that Russia's advance has slowed this year.