Ukraine rushed reinforcements to its northeastern Kharkiv region to shore up defenses against early Friday attacks from Russian forces — a move Kyiv had been expecting for weeks.

In a Google-translated post via Telegram, Ukraine's Defense Ministry said Russian forces tried to break through Ukraine's defense line around 5 a.m. but were beaten back.

Oleh Syniehubov, head of Ukraine's Kharkiv region, said "the armed forces of Ukraine confidently hold their positions" and "not a single meter has been lost," CNBC reported.

In a separate post, Syniehubov said "massive" Russian shelling in the Kharkiv region had killed at least two people and injured five others, the outlet noted.

Russian attacks in eastern Ukraine have intensified in recent weeks — a strategy likely fueled by anticipation of Western military aid headed to the war's front lines.

President Volodymyr Zelenskyy said Ukraine's military had anticipated the attack — and had calibrated its response.

"Now there is a fierce battle in this direction," Zelenskyy was quoted as saying by Ukraine's public broadcaster Suspilne.

The Russian forces are trying to exploit Ukraine's shortages of ammunition and manpower before promised new support arrives.

In a Friday post on X, Zelenskyy said "not all of our partners are currently fulfilling the agreements in a timely manner," though he didn't specify those partners.

Also early Friday, Ukraine attacked an oil refinery in Russia's Kaluga region Friday, setting the facility on fire, CNBC reported, citing Russian media reports.

Vladislav Shapsha, governor of the Kaluga region, said via Telegram the fire was extinguished, but there was no immediate estimate on damage.

The Associated Press contributed to this report.

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