Australia's prime minister called Russia's invasion of Ukraine "a moment of choice for China" Monday, urging Beijing to end its tacit political and economic support for the war.

Scott Morrison pressed China to shape the actions of its Russian ally and prove that Beijing is committed to global peace and the principle of sovereignty.

"No country would have a greater impact right now on Russia's violent aggression towards Ukraine than China," Morrison told the Lowy Institute, a Sydney-based foreign policy think tank.

"The crisis that now grips Europe heralds a moment of choice for China," he said.

Presidents Vladimir Putin and Xi Jinping met in Beijing days before the war in Ukraine began, pledging friendship with "no limits".

Since then, China has avoided direct criticism of the war, expressed sympathy for Russia's justifications and refused to join Western sanctions.

Morrison accused Beijing of throwing Russia "an economic lifeline" by relaxing trade restrictions on the import of Russian wheat.

He also voiced concern that a Chinese firm may step in to replace Visa and Mastercard services that have been frozen in Russia.

"Today we even hear of UnionPay's potential involvement out of China in supporting a payment system in Russia," he said.

Morrison has led a government increasingly at loggerheads with China's leadership.

The address -- delivered remotely as the prime minister isolated at home with Covid-19 -- served as a preview of his election stump speech, with Australians set to go to the polls within the next three months.

Morrison laid out a number of concerns about China's actions closer to home, including "the militarisation of disputed features in the South China Sea" and growing tensions in the Taiwan Strait.

He also promised that his government would build a new submarine base on Australia's east coast in the wake of his country joining the AUKUS partnership alongside the United States and Britain.

A key element of the partnership is the transfer of knowledge from the US and Britain about nuclear-powered submarine technology -- a move that has garnered criticism from Beijing.