Prime Minister Anthony Albanese is urging Chinese leader Xi Jinping to remind Russian President Vladimir Putin of his obligations under international law when the pair meet later this week.
Mr Xi and Mr Putin are expected to meet in Uzbekistan on Thursday during a summit for a security pact dominated by their respective countries.
While China has previously refused to criticise Russia's invasion of Ukraine, Mr Albanese says it's time for Mr Xi to speak up.
"What I would like to see is anyone who meets with Vladimir Putin reminds him of the obligation that international leaders have to uphold the international rules of law," Mr Albanese said.
"And what we've seen with the Russian invasion of Ukraine is a breach of that ... the invasion of a sovereign state, in contravention of international laws.
"The idea there would be a land war in Europe, of the type that we're seeing, is something that we had hoped we had consigned to the past."
Russia's foreign affairs adviser Yuri Ushakov has previously noted China's "well-balanced approach to the Ukrainian crisis", adding it understood why Russia had taken the action it did.
The two leaders will converse at a Shanghai Cooperation Organisation meeting, the security grouping between them that also includes India, Pakistan and ex-Soviet Central Asian nations.
Mr Albanese reaffirmed Australia's support for Ukraine, praising its "courageous struggle" against Russia's invasion.
"It's coming at a great human cost to the people of Ukraine," he told reporters.
"They are engaged in an inspirational struggle, which is in the interest not only of the people of Ukraine, it is in the interests of all who believe in an orderly, global process and the international rule of law."