The leaders of Fiji and Australia has signed two agreements in Suva.
The Vuvale Union Treaty, regarding economic and security, and the Ocean of Peace Alliance, a mutual defence agreement.
In a statement, Australia's Prime Miniser Anthony Albanese said these treaties represent one of the most significant endeavours Australia has undertaken with any country.
He said the two nations will build on the their longstanding history of standing together to support one another and the region's security.
They will build the Pacific's capability to tackle security challenges affecting the whole region, including transnational crime and climate change.
"This level of ambition is possible because Australia and Fiji are Vuvale - family - with a relationship grounded in trust, loyalty, understanding and respect," Albanese said.
"Australia was honoured when Prime Minister Rabuka proposed Fiji's first alliance - the Ocean of Peace Alliance.
"The Vuvale Union sets out ambitious commitments across the breadth of our bilateral relationship, including security, economy and people."
