Australian officials have joined representatives from more than 30 countries at the United Nations' highest court as Ukraine challenges Russia's claims its invasion was carried out to prevent genocide.
Days after Russian forces invaded Ukraine in February 2022, Ukrainian officials filed a case to the International Court of Justice alleging Russian leaders were abusing international law by using false claims of genocide in eastern Ukraine to justify its invasion.
Russian representatives have continued to accuse Ukraine of committing genocide.
Foreign Minister Penny Wong says there needs to be a broader discussion about reforming the UN Security Council as the Kremlin continues to use its veto power to prevent action against it.
"The fact is that we didn't contemplate, humanity didn't contemplate, that a member of the P-5 permanent members of the Security Council ... would use that veto to protect their own breach of the UN charter," she told reporters in New York on Thursday.
The council's permanent members - the US, UK, China, France and Russia - each have a veto that can prevent the adoption of resolutions.
Senator Wong said Australia backed reforms needed to ensure the UN better responds to the needs of the contemporary international community and backed an expansion of the security council.
"It doesn't reflect the economic and geopolitical configuration that we see in the world today," she said.
"So it would benefit from reform but that's a discussion that countries of the world would need to have together."
Officials from 32 countries - including Cyprus, France, Germany, the United Kingdom, Canada and New Zealand - delivered interventions in support of Ukraine at The Hague's Peace Palace.
Solicitor-General Stephen Donaghue delivered Australia's intervention and argued the court had jurisdiction to hear the case.
Attorney-General Mark Dreyfus says false allegations of genocide undermine the rules-based international order.
He said Mr Donaghue's intervention "demonstrates Australia's unwavering commitment to upholding fundamental rules of international law and the integrity of the Genocide Convention".
Australian officials have continued to call on Russia to immediately withdraw its military forces from Ukraine, in compliance with the International Court of Justice's March 2022 order.
Since the invasion, Australia has given Ukraine more than $790 million in aid, including $610 million in military equipment.