Annual Test blockbusters between northern and southern rugby superpowers are one step closer to reality after World Rugby agreed to push ahead with the so-called World League concept in Dublin last week.

But there's one big catch: Australian rugby fans may never see a 'World League' final on home soil under a model in which the competition would be played during the existing June (July from 2020) and November Test windows.

Mouth-watering match ups such as the Ireland vs All Blacks Test could become annual occurrences. Credit:AP

Officials in Australia and New Zealand have declared it is "full steam ahead" on the concept after a World Rugby working group found there was enough global broadcast interest to push ahead with a detailed feasibility study.

The group will report back to the World Rugby Executive Committee in late January on the post-2019 concept. But after agreeing that any change to the existing international windows was off the table, it appears any final or finals series would always be played in November and, thus, in the northern hemisphere.