SA says time for subs to be built locally

South Australia's Defence Minister has rejected federal government claims about time constraints for designing and building the next generation of submarines in Australia.

Federal Defence Minister David Johnston was asked on Sky News on Monday whether he would honour his pre-election commitment to build the next generation of 12 subs in Adelaide.

He said the government had to "come up with a solution that solves the time-schedule problem" and that there was "an enormous degree of urgency".

SA's Defence Minister Martin Hamilton-Smith said the claims about the timeframe were an attempt to distract Australians from the broader issue.

"The Federal Government said no decision has been made on the future of our submarines, but these statements by Mr Johnston only give the impression that a decision has been made," he said in a statement on Tuesday.

"It is clear that Mr Johnston is failing to listen to a growing list of defence and economic experts who have publicly stated that there is time for a project definition study, an open competitive tender and a considered decision on the future of our submarines."

Japan is understood to be the favoured builder of the subs.