The idea of a trans-Tasman bubble is gaining momentum -- but it's unlikely it'll happen anytime soon.

Foreign Minister Winston Peters has hinted travel to Australia for business could start more quickly that we think.

Peters says he's open to starting on a state-by-state basis.

But, Finance Minister Grant Robertson says while an arrangement could happen in future, Kiwis shouldn't expect to be freely travelling back and forth to Australia yet.

Epidemiologist, Professor Michael Baker told the Weekend Collective it's something to look forward to but it's some distance off.

"Really it's going to be weeks before we can really have a serious discussion about opening our borders with anyone."