Australia sending 'heavy weapons' to Ukraine

Australia is sending "heavy weapons" to Ukraine as already delivered Bushmaster military vehicles help keep the country's soldiers alive, President Volodymyr Zelenskyy says.

The Ukrainian wartime leader addressed Sydney's Lowy Institute on Thursday, condemning Russia's "nuclear blackmail", praising Australia's aid and calling on Canberra and other Western governments to keep ramping up sanctions against his country's invaders.

"The more weapons and ammunition we receive —  artillery, drones, anti-aircraft defence, anti-tank, anti-ship weapons — the more Russia feels the responsibility for violating international law and last, the aggressor will feel that he … has little room for any escalation element," Zelenskyy said, via videolink.

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There have been concerns Russia, which has already threatened to completely cut its gas supply to western Europe ahead of winter and ordered a partial troop mobilisation, would consider using smaller tactical nuclear weapons in a further escalation.

Zelenskyy said now was the time to increase sanctions, in the wake of Moscow's illegal annexation of four Ukrainian regions following Kremlin-orchestrated "referendums" Ukraine and the West rejected as a sham.

The president called on Australia and others to use their diplomatic power to influence an upcoming UN General Assembly vote to condemn the annexation.

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Referencing help already supplied by Australia, Zelenskyy said the 15-tonne, protected four-wheel-drive Bushmasters had performed "masterfully" in real combat operations. 

"They really help on the battlefield because they save us — they preserve the lives of our soldiers on the ground," he said, via a translator.

The president said Australia had been preparing a "significant package" to help the invaded nation, which has made significant gains against Russia in recent weeks.

"This process is ongoing as we speak, and I'm very grateful for that," he said.

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"I don't want to go into details on what weapons what's in this package, but it's not just small arms but some heavy weapons as well."

Ukrainian ambassador to Australia Vasyl Myroshnychenko last month told the Sydney Morning Herald he wanted Australia to supply anti-ship missiles known as Harpoons, more Bushmasters, 30 Hawkei four-wheel drives and howitzer long-range weapons.