U.S. weapons will help Ukraine liberate the Donbas, Ukrainian President Petro Poroshenko has said.

"First and foremost, American weapons will help us liberate the Donbas and return Ukrainian territories," he said in his speech at the U.S. Military Academy at West Point in New York early on Tuesday.

Poroshenko expressed regret that the issue of providing Ukraine with lethal weapons still remained controversial and unresolved.

He refuted an argument by Russian representatives that "American weapons cannot help resolve the situation in Ukraine" - "in fact, it can."

"They [Russian representatives] also use the arguments that the provision by Americans of weapons to our country will further escalate the conflict, but this is absolutely untrue. Why not take this positive decision and save more Ukrainians lives?" Poroshenko said.

He recalled that the lives of many Ukrainian servicemen had been saved thanks to cooperation with the United States, including in the sphere of humanitarian assistance.