Ukrainian President Volodymyr Zelenskyy visited troops close to front lines in the eastern Donbas region on Tuesday to mark the country's Armed Forces Day.

"Thank you for this resilience and strength. You are an outpost of our independence," he wrote in a Telegram post that carried footage of him meeting soldiers and handing out awards more than nine months after Russia's invasion of Ukraine.

"I believe that next time we will meet in our Ukrainian Donetsk and Luhansk," he said, referring to regional capitals in eastern Ukraine that were seized by Moscow-backed proxies in 2014.

"I am sure in Crimea as well," he said, referring to the peninsula that was captured by Russia and forces loyal to Moscow in 2014.

Zelenskyy did not indicate exactly where he met the troops on Tuesday.

He also recorded a separate video in which he spoke in front of a huge sign with letters saying Sloviansk, a city held by Ukrainian forces near the besieged city of Bakhmut.

Ukrainian officials say fighting is raging around Bakhmut as Russian troops seek its capture to gain a greater foothold in Donbas following battlefield setbacks elsewhere.