Australian-supplied Bushmaster armoured vehicles have "performed masterfully" on the battlefields, Ukrainian President Volodymyr Zelenskyy says.
In an address to the Lowy Institute on Thursday evening, he said he was grateful for the Bushmasters Australia had sent to Ukraine after he addressed the parliament in March.
"This equipment has performed masterfully in real combat operations," he said.
"The more weapons and ammunition we receive … the more Russia would feel the responsibility for violating international law.
"The aggressor will feel that he has little room for any escalation."
While not elaborating on exactly what arms Australia was supplying, he revealed more weapons were on the way to Ukraine.
"I don't want to go into details on what weapons … it is not only small arms but some heavy weapons as well," he said.
Mr Zelenskyy outlined two other ways Australia could continue to support Ukraine, as he warned the war in Ukraine would escalate unless the world responded strongly to Russia's invasion and annexations.
'Clear and straightforward condemnation of Russia'
On top of Ukraine's "very meaningful" defence cooperation with Australia, Mr Zelenskyy spoke of the continuing need for diplomatic support at the UN.
He asked for Australia to do what it could to convince as many other countries as possible not to remain neutral when the United Nations General Assembly meets next week to discuss a resolution condemning Russia's annexation of four regions of Ukraine.
Russia's total claim amounts to around 18 per cent of Ukrainian territory, though the exact borders are still to be clarified.
"There is a need for clear and straightforward condemnation of Russia for their attempts to annex Ukrainian territory," he said, via a translator.
"We must now direct our joint efforts in a way to make the vote at the General Assembly for this resolution as unanimous as possible."
Russia vetoed a condemnation in the UN Security Council last week, but in the General Assembly every country has a vote and none can veto resolutions.
Mr Zelenskyy also called for further and tougher sanctions against Russia, and thanked Australia for being part of the international sanctions applied so far.
"Now is the time to increase this pressure, when Russia has staged this sham referendum and staged this annexation," he said.
"The consequences must be tough."
'We know what neighbours we have'
In response to President Putin's annexation of Donetsk, Luhansk, Kherson and Zaporizhzhia, the biggest expansion of Russian territory in at least half a century, Mr Zelenskyy has applied for fast-track membership of NATO.
The Ukrainian leader also said Kyiv remained committed to the idea of co-existence with Russia "on equal, honest, dignified and fair conditions", but that it was unlikely while Mr Putin remained in power.
When asked if he had received a response from NATO, Mr Zelenskyy said without Ukraine, NATO was not as strong as it could be.
"We know what neighbours we have, what risks we have," he said.
NATO needed to demonstrate that it was not afraid of Russia, he added.
While not giving a direct answer or time frame, he did indicate that Ukraine was still waiting to hear from NATO.
"How fast [membership approval] is going to be, unfortunately it depends not only on Ukraine," he said.
