Part two of Christiane Amanpour's interview with President Poroshenko, on corruption and freedom of the press, airs on Friday.

(CNN) On the day of his country's 25th anniversary of independence from the Soviet Union, Ukrainian President Petro Poroshenko is warning that Russian President Vladimir Putin wants "the whole Ukraine" to be part of the "Russian Empire."

"It is absolutely the same situation like Russian bombardment in Aleppo," he told CNN's Christiane Amanpour in an exclusive interview Wednesday.

"They have only one purpose -- [the] world should be less stable, less secured."

JUST WATCHED What a ceasefire in Ukraine looks like Replay More Videos ... MUST WATCH What a ceasefire in Ukraine looks like 03:28

ceasefire deal reached last year in Belarus -- the so-called Minsk agreement -- is a distant memory in eastern Ukraine, where CNN witnessed intense fighting in the last several days.

Unrest there has been on the rise, and Russia has recently conducted military drills in Crimea, the peninsula it annexed from Ukraine in 2014 -- a move most nations do not recognize as legitimate.

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