Beijing trumpeted Nauru's move in January to switch diplomatic ties to China from Taiwan, amid a tussle for influence in the Pacific Islands, where the Asian giant's growing police presence has raised concern in Australia.
China pledged $A15 million in direct budget support to Nauru in 2024, although the money had not been received by October, a Nauru government budget update showed.
Australia's anxiety about China's security ambitions in the Pacific Islands grew after Beijing fired an intercontinental ballistic missile with a dummy warhead into the Pacific Ocean in September.
A Nauru government official confirmed to Reuters there were talks between President David Adeang and Australia on a migration deal.
On Wednesday, Australia's Sydney Morning Herald newspaper reported that Canberra wanted a pact with Nauru that prevented China gaining a security foothold.
"The talks are still under way," said the Nauru government spokeswoman, declining to give further details.
Australia's Department of Foreign Affairs and Trade did not respond to a request for comment, and other Australian officials declined to comment.
The speaker of Nauru's parliament, Marcus Stephen, met China's top political adviser, Wang Huning, in Beijing on Tuesday, state news agency Xinhua said.
Adeang travelled to Australia to meet Prime Minister Anthony Albanese in May and June after a March visit to Beijing to meet President Xi Jinping.
Australia's Regional Processing Centre for asylum seekers, hosted in Nauru, accounted for three-quarters of government revenue collection in 2024, and is forecast to contribute $A209 million in 2024/25, the budget update showed.
Australia has also pledged aid of $A46 million in 2024.
In the 1970s Nauru was among the world's richest nations per capita because of phosphate mining, despite a small land area of 21 sq km.
The nation of 12,000 people fell into debt two decades later.
Ministers from Nauru visited China in November to discuss phosphate exports, and financial arrangements with the Bank of China, Nauru statements show.
