Australian Defence Minister Peter Dutton, British High Commissioner Victoria Treadell and U.S. Chargé d'Affaires Michael Goldman signed the documents at Parliament House in Canberra.
"This is the first time that the U.S. and U.K. will have shared this information with a third country, ever. That was something worth securing. That was something Australia has long sought and our government has secured," Australia's Prime Minister Scott Morrison told reporters in Canberra.
Australia in September canceled a deal with France's Naval Group, opting instead to build at least 12 nuclear-powered submarines in a deal with the United States and Britain. The new alliance, dubbed AUKUS, is designed to give Australia access to nuclear-powered submarines for the first time.
The decision has caused a major bilateral rift, with France recalling its ambassadors from Australia and the United States in protest.