Australia will buy three Virginia class nuclear-powered submarines with the option to buy two more, White House national security adviser Jake Sullivan said on Monday.

U.S. President Joe Biden, Australian Prime Minister Anthony Albanese and British Prime Minister Rishi Sunak were set to unveil details of the so-called AUKUS project on Monday at the U.S. naval base in San Diego, California, principal home port of the U.S. Pacific Fleet.