South Australian Senator Rex Patrick has told Sky News the government should consider “walking away” from its “mess” of a French submarine contract.

Australia currently has a contract with French manufacturer Naval Group to convert 12 nuclear submarines to normal diesel engine submarines which are not expected to be ready until around 2035.

The Morrison government has appointed two former senior naval officers to review the program, which is running over-budget and set to run over-schedule, according to the Australian Financial Review.

Mr Patrick said Australia originally set out to acquire a “regionally superior submarine” but by 2035, the French submarines’ performance will be problematic.

“Performance wise, it’s problematic; it’s running late; it’s not meeting expectation in terms of Australian industry content,” he said.

“We may get to a point in 2035, 2040 where the submarine hasn’t been delivered and the cost blows out by let’s say ten per cent at best.

“That leaves us with a $10 billion deficit and that will have to come from other capability, other navy capability, other army capability other air force capability”.

Mr Patrick said the government should consider following the likes of South Korea and Greece and buy up to 20 submarines off the shelf which could provide the country with “highly capable” subs by 2028.

“The government should be considering walking away from this contract.”