Australia will buy three nuclear-powered submarines from the US in the next decade before building a new class of submarine with Britain using US nuclear propulsion technology around 2040 through the Aukus partnership.

Legislation introduced to parliament last month establishes a regulator to ensure safety for the nuclear-powered submarine programme. It does not alter Australia’s moratorium on civil nuclear power, the government said.

The Australian Naval Nuclear Power Safety Regulator will monitor and enforce safety over the next decade, the government said.

The Aukus partnership to develop nuclear-powered submarines and other high-technology weapons is Australia’s most expensive defence project, with a US$244 billion price tag over three decades.