KYIV, Ukraine — Ukrainian forces have secured “combat control” of areas where Russian troops entered the northeastern Kharkiv region earlier this month, President Zelensky says.

“Our soldiers have now managed to take combat control of the border area where the Russian occupiers entered,” Mr. Zelensky said in his nightly video address on Friday evening.

Mr. Zelensky’s comments appeared to be at odds with those made by Russian officials.

A member of Russia‘s lower house of parliament, Viktor Vodolatskiy, said Russian forces now controlled more than half of the town of Vovchansk, three miles inside the border, Russian state news agency Tass reported Friday.

Vovchansk has been a flashpoint for fighting since Russia launched an offensive in the Kharkiv region on May 10.

Mr. Vodolatskiy was also quoted as saying that, once Vovchansk was secured, Russian forces would target the cities of Sloviansk, Kramatorsk, and Pokrovsk in the neighboring Donetsk region.

No independent confirmation of the claims was immediately possible.

Russia’s Kharkiv push appears to be a coordinated new offensive that includes testing Ukrainian defenses in the Donetsk region further south, while also launching incursions in the northern Sumy and Chernihiv regions.

President Putin has said the Kremlin’s army is attempting to create a “buffer zone” in the Kharkiv region to prevent Ukrainian cross-border attacks.

The city of Kharkiv, which is the capital of the region of the same name, is about 12 miles from the Russian border. Moscow’s troops have in recent weeks captured villages in the area as part of a broad push, and analysts say they may be trying to get within artillery range of the city.

Ukrainian authorities have evacuated more than 11,000 people from the region since the start of the offensive.

The Russian push is shaping up to be Ukraine’s biggest test since Moscow’s full-scale invasion in February 2022, with outnumbered and outgunned Ukrainian forces being pressed at several points along the about 620-mile front line that snakes from north to south in eastern Ukraine.

Ukraine’s problems have been mounting in recent months as it tries to hold out against its much bigger foe, and the war appears to be at a critical juncture.