Rick Springfield’s repping his Aussie roots ... and he’s coming in strong with some hot and heavy advice for Nicole Kidman and Keith Urban now that they’ve officially gone their separate ways.

We caught up with the icon at LAX Monday ... and he tells us the newly divorced duo should have just one thing on their minds as they start their single lives -- and that’s getting laid. A lot!

Rick was fully Team Single Life for Australia’s former royal couple ... who totally blindsided everyone with their split back in September.

You’ve gotta watch the clip ... 'cause he also goes off about other Down Under essentials, like Vegemite, beer, and that accent.

It’s all koala-ty stuff ... hop to it and check out our chat with Rick!