"As of now, the situation in the Kharkiv region is generally under control," Zelensky said on social media from the regional capital of the same name, quoted by the French agency AFP.

"But the area remains extremely difficult, which is why we are reinforcing our units," he said.

Zelensky met with the region's military commanders, according to the Ukrainian agency Ukrinform.

He heard detailed reports on the operational situation and the needs of each unit in the Kharkiv region, particularly in the Vovchansk and Liptsiv districts.

Zelensky said they also analyzed the prospects of the combat situation, the threats in the coming days and weeks, and the Ukrainian opportunities to counter the Russian offensive plans, according to Ukrinform.

"A plan of future actions has been defined, both for the Kharkiv regional authorities and for all structures responsible for security in the region," Zelensky said.

But the situation "continues to be extremely difficult, we are reinforcing our units," he added.

Russia on Friday launched a surprise offensive against Kharkiv, Ukraine's second-largest city, the capital of the region of the same name located near the border between the two countries.

Zelensky this week ordered reinforcements to be sent to Kharkiv and canceled all foreign commitments in the coming days, including trips to Spain and Portugal.

The Ukrainian leader on Tuesday asked the United States for two more "Patriot" missile systems to defend Kharkiv, during a meeting in Kyiv with US Secretary of State Antony Blinken.

Since it was invaded by Russia in February 2022, Ukraine has received financial and military aid from Western allies, but has also criticized hesitations and delays in sending weapons.

Kyiv's allies have also imposed successive packages of sanctions on Russian interests to try to diminish Russia's ability to finance the war effort in Ukraine.

[News updated at 12:01 pm]

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