Ukraine's President Volodymyr Zelensky has said that the situation is becoming increasingly difficult near the eastern Ukrainian town of Bakhmut.
He said: "In the Bakhmut sector, the situation is constantly becoming more difficult."
Zelensky added: "The enemy is constantly destroying everything that can be used to protect our positions for fortification and defence."
Bakhmut is a hot point in the conflict, where some of the fiercest fighting of 12 months has taken place and claimed countless Ukrainian and Russian lives and left entire districts as smoking piles of rubble.
The town, part of which is under the control of Russia and its separatist fighters, has seen intensified fighting recently as both sides battle for full control.
Recent Russian efforts have lead to Putin's troops gaining ground, potentially signalling that the tables could be turning after 12 months of military humiliation.
Dennis Pushilin, the leader of the self-proclaimed Donetsk People's Republic (DPR), says that most of the roads leading in and out of the industrial city are under the control of Russian forces.
Ukrainian ground force commander Col Gen Oleksandr Syrskyi echoed his enemies comments, saying the situation is "extremely tense".
"Despite significant losses, the enemy threw in the most prepared assault units of Wagner, who are trying to break through the defences of our troops and surround the city," Gen Syrskyi said.
The president said Ukraine's ability to defend the city was being compromised by the unrelenting Russian onslaught.
He said he's "grateful to each and every person who is heroically holding" the area.
Mr Zelensky reissued calls for modern combat aircraft from Ukraine's western allies to defend the country from "Russian terror".
A video has emerged showing the once-bustling city destroyed to an apocalyptic landscape of charred tree trunks and smoking rubble.
The FT's Ukraine correspondent Christopher Miller wrote on Twitter: "My god. I know every location in this video. It’s central Bakhmut.
"The mosaic building housed the Vesna market where I would pick up groceries. My apartment was 100 feet away.
"Bakhmut has descended into urban warfare and pure hell. Heartbreaking."
