American submarines will visit Australia more regularly but Defence Minister Richard Marles has rejected basing them down under to bolster our defences until our nuclear-powered boats hit the water.

Mr Marles is planning to use this week’s first meeting of AUKUS defence ministers to lock in the key planks of Australia’s nuclear submarine plan before it is unveiled early next year.

But he said home-porting US submarines in Australia was “not the answer” to covering any capability gap that emerged before our boats were in service.

This week’s AUSMIN meeting between Australian and US defence and foreign affairs ministers is also likely to lock in an expanded US Marine rotation in Darwin, and potentially the deployment of more US aircraft including nuclear-capable B-52 bombers.