Further military support for Ukraine will be a central pillar of a key NATO conference Australia is attending, as the defence minister works to shore up allies' commitment to the Pacific.
Australia is set to announce a new support package for Ukraine, days after a deadly missile barrage destroyed a children's hospital in its capital Kyiv.
Ukrainian President Volodymyr Zelenskiy has asked allies for more air defences.
Assistant Defence Minister Matt Thistlethwaite foreshadowed the new package ahead of its announcement in coming days, saying Australia would extend its efforts to help Ukraine repel Russia.
"Australia's been a great contributor, and will continue that contribution for as long as it's needed," he told ABC Radio on Wednesday.
Defence Minister Richard Marles said it was important NATO members continued to support Ukraine.
"We see this as a conflict that is likely to endure over a period of time and we certainly will be standing with Ukraine for as long as it takes," he told reporters in Washington.
He also defended American leadership on Ukraine amid concerns over what a future Trump presidency could mean for the embattled nation.
But the defence minister would not be drawn on speculation.
"I'm not going to go into commentary about what may or may not happen," Mr Marles said.
"It matters that we see support for Ukraine and that will continue to be our position and it will continue to be our advocacy."
Mr Marles is expected to meet with Mr Zelenskiy during the summit.
The North Atlantic alliance also matters to the Indo-Pacific as partners work to protect the status quo and international law, the defence minister said.
"Things like the UN Convention on the Law of the Sea, on concepts such as freedom of navigation," he said.
"NATO matters to us because that is central to the ethos of NATO."
Australia's invitation to the summit underscores that the primarily US-European alliance was also focused on the Pacific, Mr Thistlethwaite said.
Opposition foreign affairs spokesman Simon Birmingham called on the government to tighten security ties by further integrating Australia into NATO.
"Australia should be there, not just to attend, but with a plan for how we make NATO a more central partner in our regional security and in the peace we want for our region," he said.
"That should be us asking NATO to develop its own Indo-Pacific strategy and seeking to formalise the ties between the so-called Indo-Pacific four nations and NATO so that we aren't just invited each year, but we're embedded as part of these critical security talks."
Australia, Japan, New Zealand and South Korea make up the Indo-Pacific four, who have each sent a delegation to Washington.
Mr Albanese was expected to attend the summit but deferred to his second-in-command, in order to focus on domestic matters.
The opposition has criticised the move, but the government insists it was the right call.
"The focus of this one is very much on defence, so that's why you've got the defence minister here representing Australia," Mr Thistlethwaite said.
