Russia regards the planned supplies of F-16 fighters to Ukraine as a "signal action" by NATO in the nuclear area, Russian Foreign Minister Sergei Lavrov told the RIA news agency in an interview Thursday.

"They are trying to tell us that the United States and NATO would stop at nothing in Ukraine," Lavrov said after noting the F-16 fighters were nuclear-capable.

Ukraine will receive its first supplies of F-16 fighter jets "very soon," but around half of its desperately needed foreign military aid is arriving late, Kyiv's defense minister has said.

Rustem Umerov, 42, told Reuters in an interview in Kyiv late Monday that Russia was deploying more manpower and equipment to the front, more than 27 months after its full-scale invasion.

Kyiv's forces have managed to stabilize the new front in the northeastern Kharkiv region where Russia attacked earlier this month. But Umerov said Moscow was preparing for a new push.

"Their objective is to open a new front in the north to start using all their manpower, firing power, against us, they are continuing with their objective to destroy the nation," he said.

"We are withstanding, but of course we need more weapons, we need more firing power, we need long-range missiles, not to allow them to enter our state."

He said Ukraine was grateful for the military aid and weapons supplied by its partners, but that only half of the promised deliveries arrived on time. Every delay benefited Ukraine's much larger and better-equipped foe, with a front line stretching 1,200 km (750 miles).