New Delhi: Three weeks into the invasion by Russia, the Ukrainian forces have now reportedly started gaining battlefield momentum in some key areas of the country to reclaim ground from the Russian military, a Pentagon spokesman said on Tuesday.
According to reports, the Ukrainian army - backed by military aid by several Western nations including the United States - has now gone into attack mode and is retaliating by pushing Russian forces back.
Ukraine has been unexpectedly fierce, and now the Ukrainians are "in places and at times going on an offensive," Pentagon spokesman John Kirby told CNN.
"They are going after Russians and pushing them out of places where the Russians have been in the past," he said, particularly in Mykolaiv, in the south.
"We have seen this now increase over the last few days," Kirby added.
The US, however, has not got any official confirmation from Ukrainian officials that they had retaken at least one town and expect to take more in the coming days. But it would be "consistent with the kind of fighting and the kinds of capabilities we have seen the Ukrainians use," he said.
Hitting out at Russia, Kirby said, "They are running out of fuel. They are running out of food. They are not integrating their operations in a joint manner the way you would think a modern military would."
The Russians are "frustrated" and "stalled," he said, citing the fact the Russians have failed to take control of population centers beyond two areas around Kherson and Melitopol in the south.
The remarks from US official came hours after Ukrainian President Volodymyr Zelensky made it clear that Russia's ultimatum to end the ongoing war can only be met if entire Ukraine was destroyed.
Earlier in the day, Ukraine defiantly rejected a Russian demand that their forces in Mariupol lay down arms.
Putin Changes Tactics For Ukraine Invasion
After failing to capture Kyiv even after four weeks since Russia began its military offensive against Ukraine, Vladimir Putin has now been forced to change his war tactics and is moving to a strategy of "protecting key territorial goals", The Wall Street Journal reported on Monday.
Russian troops have been shelling Kyiv for a fourth week now and are trying to surround the capital, which had nearly 3 million people before the war.
Now the Russian President wants to force Kyiv to accept Moscow's claims to the southern and eastern territories of Ukraine.
Several rounds of talks between Russia and Ukraine have taken place, but it failed to bridge the chasm between the two sides. While Russia remains stern on its demand of Ukraine disarm, Zelenskyy pressed his condition of complete withdrawal of Russian forces from his country.
(With inputs from agencies.)