Ukrainian President Petro Poroshenko has called on Russia to recognize the famine that killed millions of people in Ukraine under Soviet dictator Josef Stalin as genocide, "or at least repent for it."

Poroshenko made the call at an event in central Kyiv on November 25, the official Day of Remembrance of the Victims of the Holodomor.

He also said that "the time has come" for Ukraine to adopt legislation against denying the genocide.

"Not recognizing the Holodomor is as immoral as denying the Holocaust," the president said.

Ukraine and about a dozen other countries have recognized the famine as an act of genocide against the Ukrainian people.

The Day of Remembrance for the victims of the famine is marked in Ukraine every year on the fourth Saturday of November.

The Holodomor took place in 1932 and 1933 as Soviet authorities forced peasants in Ukraine to join collective farms by requisitioning their grain and other foodstuffs.

Historians say the seizure of the 1932 crop in Ukraine by Soviet authorities was the main cause of the famine. Moscow has long denied any systematic effort to target Ukrainians, arguing a poor harvest at the time wiped out many in other parts of the then Soviet Union.

It is estimated that as many as 9 million people may have died as a result of executions, deportation, and starvation during the Stalin-era campaign.

Poroshenko on November 25 urged “all political forces” in Ukraine to unite for the sake of the country, saying the Holodomor was "a terrible echo of an unforgiving loss" of Ukrainian statehood and independence.

"Would the Holodomor and the great terror of the 1930s, the deportation of the 1940s, and the Russification of the 1970s be made possible if we, Ukrainians, had preserved the independence proclaimed a hundred years ago?" he asked.

Poroshenko also said that Russia's ongoing "aggression against us is a continuation of the same policy to destroy Ukraine with other methods."

Meanwhile, Oleksandr Turchynov, chief of the National Security and Defense Council, said in a statement that "there is a war and we again see manic attempts to destroy Ukraine."

Moscow seized control of Ukraine's Crimean Peninsula in March 2014 and fomented separatism across eastern and southern Ukraine -- one of the causes of a war that has killed more than 10,000 people in eastern Ukraine since April 2014.

Russia denies it has sent troops, weapons, and other support to help the separatists fight government forces in eastern Ukraine, despite what Kyiv and NATO say is incontrovertible evidence.

With reporting by AFP