Ukraine on Tuesday said the International Court of Justice should impose reparations on Russia for its "war of annihilation", arguing that international law itself was at stake.
"Russia is not above the law. It must be held accountable," Ukraine's lead speaker, Anton Korynevych, told the court, sitting just a few metres from his Russian opponents in the Peace Palace in The Hague.
"You have the power to declare that Russia's actions are unlawful, that its continued abuses must stop, that your orders must be followed and that Russia must make reparations," he told the judges.
He later told reporters the exact amount of reparations Ukraine would demand needs to be worked out at a later date, but that Kyiv would use every opportunity in international courts to "prove that the Russian Federation is the biggest violator of international law in the 21st century."
Ukraine dragged Russia before the ICJ only a few days after the February 24, 2022, invasion, seeking to battle its belligerent neighbour on all fronts, legal as well as diplomatic and military.
Kyiv's argument is that Russian President Vladimir Putin invoked a supposed "genocide" against pro-Russian people in eastern Ukraine as one of the reasons for Moscow invading its neighbour.
This, according to Ukraine, is a misuse of the United Nations Genocide Convention, set up in 1948 and signed by both Kyiv and Moscow.
"At our moment of greatest peril, Ukraine turned to this court. Your court has broad jurisdiction over disputes relating to the Genocide Convention," argued Korynevych.
"Can it truly be the case that a state can abuse the Genocide Convention to justify a war of conquest?" asked Korynevych.
"It must be 'no' for the sake of the world, to prevent international law from being twisted into a tool for human right abuses and destruction," he added.
In a preliminary ruling in March last year, the ICJ sided with Ukraine and ordered Russia to halt its invasion immediately.
But Russia objected to this judgement, saying the ICJ had no legal right to decide in this case.
"Russia's defiance is also an attack on this court's authority. Every missile that Russia fires at our cities, it fires in defiance of this court," said Korynevych.
- 'Hopelessly flawed' -
The hearings now underway in the Peace Palace centre around whether or not the ICJ has jurisdiction.
Russia's legal team argued on Monday that the case should be thrown out.
If Kyiv denies there is a genocide in eastern Ukraine, why is the court even considering a case under the Genocide Convention, runs Moscow's argument.
Mere "statements" about genocide are not admissible under international law including the Genocide Convention, Russia's lead representative Gennady Kuzmin contended on Monday.
Ukraine's legal position is "hopelessly flawed" and "at odds with the longstanding jurisprudence" of the court, he concluded.
Using longstanding Russian talking points, he also accused the Kyiv "regime" of being "firmly entrenched in the history, doctrines and practises of Nazism", comments seized upon by Ukraine's envoy.
"The (Russian) agent had the audacity to stand in this court and say that Ukraine was planning 'final solutions'. We all know what those chilling words mean.
"How can Russia's agent utter those words and then deny that there is a dispute about genocide?" said Korynevych.
In addition to the two warring countries, 32 allies of Ukraine will also take the floor on Wednesday, arguing in support of Kyiv.
The ICJ was set up to settle disputes between countries but is not famed for the speed of its work. The court is likely to take months just to decide whether it can hear the case.
Its rulings are binding although it has no way of enforcing them.