Mr Morrison has called on China to be transparent about its relationship with Russia as the United States raised concerns about the prospect of financial and military aid flowing through to the Kremlin.

"What is their relationship with Russia, when it comes to throwing them an economic lifeline during this global crisis? And potentially, what, if any, support has been discussed for military support for Russia?" Mr Morrison said.

"Because that would be an abomination."

The prime minister said he remained disturbed by the "chilling silence" echoing in Beijing following Russia's invasion of Ukraine.

The former director of the Defence Intelligence Organisation says Australia shouldn't underestimate the relationship as the pair operate in a quasi-alliance.

Russia was supplying Beijing with high-performance, leading-age technology, including quiet diesel-electric submarines and one of the world's best air defence systems, Professor Paul Dibb said.

Russian President Vladimir Putin also agreed to build China a ballistic missile early-warning radar, which would make America's capacity to penetrate nuclear missiles into China a bit more complicated, Prof Dibb told the National Press Club on Wednesday.

He said the Chinese president would closely monitor Western actions against Russia and assess how aggressive it could become towards Taiwan without provoking retaliation.

"Xi Jinping will be scrutinising in exquisite detail how much Putin is getting away with the use of military force against a sovereign country across sovereign boundaries," he said.

Labor foreign affairs spokeswoman Penny Wong said China needed to demonstrate its support for its foreign policy pillars of non-interference and sovereignty.

"China does have a choice to make," she told a United States Studies Centre forum.

"We would expect it to do the responsible thing and support the people of Ukraine and its sovereignty, and not supply weapons to Russia."

Senator Wong also used a meeting with the new Chinese ambassador Xiao Qian to urge Beijing to use its influence and lean on Moscow to end the war in Ukraine.

But Beijing was unlikely to push Russian support too far and risk escalating tensions with the US, former defence department secretary Dennis Richardson said.

"China will support Russia, but I think it will measure out the support in a way that probably keeps it below what might be the sanctions threshold for the US," he said.

"China will operate in a grey area, in a murky area, and it will be difficult to actually catch China with its hands in the till sufficient for sanctions to be imposed."

While unambiguous support for Russia may appear improbable, decoupling the so-called "unholy alliance" between the authoritarian states with threats is equally unlikely, according to Prof Dibb.

"The issue is we obviously can't now have any prospect in the long foreseeable future of detaching Russia," he said.

"Can we somehow detach China? I'm going to say, my initial reaction to that is - dream on."

But Prof Dibb said the West 's co-ordination in sanctioning Russia made it more complicated for the Chinese president to act on Taiwan.

"I never thought that the West would get its act together like that," he said.

"Putin views Europe as weak and divided (and) until recently would have every reason to believe that. He (also) views the US as a declining power, as does his great ally Xi Jinping."

Labor leader Anthony Albanese criticised Beijing for failing to condemn Russia's invasion and offering Russia economic lifelines as global sanctions began to cripple its economy.

"China has a responsibility to call out Russia's behaviour and its aggression," Mr Albanese said.

Australian Associated Press