Ukrainians can begin claiming wartime damages on Tuesday as allies consider ways to make Russia pay for its invasion.
About 600,000 people are expected to report damage to their homes in the first phase of claims.
Finding the money to compensate those who have had their homes destroyed remains an issue with Ukraine pushing for frozen Russian assets to be used as reparations.
Ukraine also wants the Russian leadership prosecuted for the crime of aggression, in what could be a difficult process.
President Volodymyr Zelenskyy addressed The Hague on Tuesday almost two years since the discovery of alleged war crimes in Bucha, near Kyiv, where bodies were found with their hands tied.
Mr Zelenskyy said holding Moscow accountable for alleged war crimes could restore security to Europe and send a message to “everyone who comes to power in Russia after Putin”.
“Every potential aggressor should know what awaits him if he ruins peace,” he said.
In a message of support to Ukraine, Dutch King Willem-Alexander said there could be “no lasting peace without justice”.
“It is unacceptable for perpetrators of international crimes to escape their punishment,” the monarch said.
The register of damage allows Ukrainians to make claims online via an app called Diia.
As many as 10 million claims are expected once the focus is widened beyond housing into personal injury and damage to public buildings.
Thousands of schools and hundreds of hospitals “either lie in ruins or are badly damaged” and more than 100,000 crimes have been documented, said Dutch Foreign Minister Hanke Bruins Slot.
However, claimants are warned that the register is only a first step towards compensation and that it is “impossible to make projections on timing”.
“Claimants must recognise and accept that it will take time before such a compensation mechanism is established,” the register’s terms outline.
Russian assets
Ukraine wants Kremlin assets confiscated to pay for damage, but Europe has not yet been willing to go further than using the interest earned by Russian funds as they idle in Belgian accounts.
The EU windfall tax is expected to generate about $2.7 billion a year to go towards Ukraine’s immediate military needs, having previously been earmarked for reconstruction.
The World Bank estimated in February that Ukraine would need $486 billion to rebuild after the war. Ukraine has said that amount could double if compensation is taken into account.
Kyiv is eager for money to be delivered while the war continues.
“Ukrainians require justice now. Not in the distant future. They do not want to hear that justice will be served. They want to see it already served,” said Foreign Minister Dmytro Kuleba.
“The world will only feel safe when Russia is held accountable for what it has done.”
Ukraine has also called for trials for the crime of aggression, defined as the use of armed force against the sovereignty, integrity or independence of another state.
However, this cannot take place at the International Criminal Court in The Hague because Russia is not a member.
Putin says Russia's goals in Ukraine have not changed
The ICC has issued an arrest warrant for Russian President Vladimir Putin in an area where it does have jurisdiction, the alleged deportation of Ukrainian children to mainland Russia.
Since the war began, Mr Putin has avoided travelling to countries where he would be likely to face arrest.
One proposal to try the crime of aggression is to set up a one-off tribunal, like the Nuremberg court that prosecuted Nazi war crimes.
The Dutch government has offered to host such a tribunal. Another option is to house a special court within Ukraine’s justice system.
Questions remain over how such a court would work, not least because Russia forbids the extradition of its citizens and would be unlikely to co-operate.
However, Ukrainian leadership is determined to show it is striving for justice for victims in Bucha and other towns and cities.
Two years ago the “unspeakable Russian atrocities revealed in Bucha and other towns in the Kyiv region shook the very moral foundation of the continent,” Mr Kuleba said.
“We will only have the right to call ourselves European when justice to them and their relatives is served.”
