China urged Australia to be cautious regarding its warming up to Japan, calling on Canberra to remember Japan's war crimes against its country and citizens during World War II.

Last September, amid experiencing tension in ties with its largest trading partner, China, due to trade differences, origins of the COVID-19 pandemic, and accusations of Chinese interference, Australia announced its intentions on strengthening the relationship as its Foreign Minister Penny Wong urged China to help end the war in Ukraine in its capacity as a "great power".

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Despite Canberra's positive reapproach to Beijing, earlier in October, Japan and Australia signed a security pact to counteract China.

The "Joint Declaration on Security Cooperation" included agreements to share sensitive intelligence and deepen defense cooperation. 

However, Australia's new left-leaning government has been attempting to ease tensions with China that arose during the previous conservative government.

The Chinese Ambassador to Australia said Canberra must remain careful about trusting Tokyo, given the latter's crimes in World War II.

"During the Second World War Japan invaded Australia, bombed Darwin, killed Australians and shot Australian (prisoners of war)," Xiao Qian said to reporters.

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"And the Japanese government has not apologised for that … does that mean they have really realised it's wrong? If they don't apologise, they don't accept it's wrong, and they might repeat the history," he continued.

Qian suggested that Canberra must "be careful about what might happen in the future. When someone threatens you, he might threaten you again."

"China has been your friend."

Aware of "disrupted" trade between the two countries (mainly coal), Xiao said he is hopeful that relations between Beijing and Canberra would go "back to normal."

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Earlier, in an interview for The Australian newspaper, Japan's Ambassador to Australia, Shingo Yamagami, warned that Tokyo and Canberra must remain "vigilant" of China.

When asked by reporters about Yamagami's statement, Qian said Japan's Ambassador was acting out of his role.

"It's not my role to base myself in Canberra while criticising third countries. It's not my role … to try and stop Australia developing normal relationship with a third country," Qian said to Journalists.

"So I'm afraid our colleague from Japan is not doing his job."