"There are food stocks, but they have not been resupplied for two weeks," Roman Vlasenko said via text message for CNN. “So stocks won't last long. If there is a humanitarian corridor, I believe people are ready to leave Azot."

Read here Intense fighting continues inside Severodonetsk, – Ukraine’s Ministry of Defense

In an interview on national television, the head of the city’s military administration said that travel between Ukrainian-held Lysychansk and Severodonetsk was difficult but still possible.

"Ways to escape are quite dangerous, but they exist," Oleksandr Striuk said. "It is wrong to say that the city is completely cut off. Logistics has become much more complicated."

Striuk said that it was difficult to estimate how many civilians were left in the city, saying only that there were around 10,000 people left "at the beginning of the escalated situation."