"Everyone should know that, by and large, we haven't started anything yet in earnest," he said in an aggressive speech to parliamentary leaders.
"Today we hear that they want to defeat us on the battlefield. What can you say, let them try," he further said.
"We have heard many times that the West wants to fight us to the last Ukrainian. This is a tragedy for the Ukrainian people, but it seems that everything is heading towards this," he added, reported by Reuters.
He, however, did not reject the idea of peace talks. "At the same time, we don't reject peace talks. But those who reject them should know that the further it goes, the harder it will be for them to negotiate with us," he asserted.
The warnings come at a time when Russia tights its grip on the Donbas region.
Russian forces claimed a few days ago to have full control over the key city of Lysychansk, which was serving as the last major Ukrainian stronghold in the Luhansk region in the eastern part of the country.
Controlling Lysychansk means effectively controlling the Luhansk Oblast, given that the other key city, Severodonetsk, fell to Russian troops a few days ago. With Luhansk under Russian occupation, Donetsk becomes the next target.
Meanwhile, the crackdown on anti-war protesters continues in Russia.
A opposition councilor Alexei Gorinov, who was first detained in April, will face prison for spreading “knowingly false information” about the Russian Army.
In the court, he held up a piece of paper that read, 'Do you still need this war'?
“War, whatever synonym you call it, is the last, dirtiest, vile thing, unworthy of the title of a man,” Gorinov said in this closing statement, reported by The Guardian.
(With inputs from Reuters and The Guardian.)