Ukrainian President Viktor Yushchenko has called on the international community to recognise the 1930s Great Famine as Soviet-enforced genocide.
A quarter of Ukraine's population was wiped out in just two years
"The world must know about this tragedy," he said, at the opening of an exhibition dedicated to famine victims.
Millions of Ukrainians starved to death in 1932-33 as USSR leader Joseph Stalin stripped them of their produce in a forced farm collectivisation campaign.
A small number of nations have already recognised the famine as genocide.
Ukraine has designated 26 November as an official day of remembrance for victims of "Holodomor" - meaning murder by hunger - and other political crackdowns.
Called Holodomor in Ukrainian - meaning murder by hunger
About a quarter of Ukraine's population wiped out
Seven to 10 million people thought to have died
Children disappeared; cannibalism became widespread
There are plans to mark the anniversary this Saturday by lighting 33,000 candles - representing the number of people thought to have been dying every day at the height of the famine.
The true scale of the disaster was concealed by the Soviet Union, and only came to light after Ukrainian independence in 1991.
Cannibalism is reported to have become rife as a whole nation starved.
The tragedy should "become a lesson for our nation as well as for the whole world", Mr Yushchenko said on Friday.
In 2003, marking the 70th anniversary of the famine, the UN said the famine "ranks with the worst atrocities of our time" and a national tragedy - but left out any reference to genocide.
Roman Serbyn, professor of history and a Ukrainian expert at the University of Quebec in Montreal, says: "Ukraine did not make a technically clear case."
Farmers' produce was forcefully collected by the state
He believes the "genocide" designation has proved elusive because the famine is often considered to have been aimed at a social group (peasants) rather than a national or ethnic group.
However, a strong case can be put showing that by closing the borders so Ukrainians could not escape to Russia, Stalin was targeting Ukrainian nationals, he says.
Russia opposes designation as genocide, he says, and "the biggest reason is national pride. But also the political and economic consequences... if you recognise a crime you might have to pay compensation".
In 2003 Russia's ambassador to Ukraine, Viktor Chernomyrdin, was quoted by Interfax news agency dismissing talk of an apology or compensation, saying: "We're not going to apologise... there is nobody to apologise to."