The Australian Government has plans to seek help from the US to build 12 conventional submarines, according to Defence Minister Stephen Smith.

The building of the so-called ‘Future Submarine’, intended to replace the navy’s six troubled Collins Class boats at an estimated cost of $36bn, will be Australia’s biggest defence project to date.

The Australian has reported the minister as saying that nuclear-powered submarines were not an option for Australia.

The proposal will be discussed with the new US Secretary of Defence Leon Panetta and other senior officials along with Australian Defence Department secretary Ian Watt, and Australian Defence Force chief General David Hurley.

Currently, the US Navy operates only nuclear submarines.