'This is not a charity': Ian Foster's thoughts on the future of Super Rugby

All Blacks coach Ian Foster says future Super Rugby competitions can't afford to carry weak links, heightening the likelihood Australia won't be offered equal rights in New Zealand's proposed model.

Findings from NZ Rugby's review into a future competition structure will be made public on Thursday, with its recommendation expected to feature all five Kiwi franchises in an eight-team competition.

Only two or three Australian sides are likely in the preferred model, with a Pacific Islands team possibly introduced.

Rugby Australia has said it won't accept a reduction in the number of Australian teams and has threatened to abandon an Australasian alliance and launch its own competition.

Former All Blacks coach Steve Hansen last week said NZ Rugby owed nothing to its trans-Tasman rivals and his successor Foster took an equally hard-nosed approach, questioning whether Australia had the player depth and financial strength to field up to five teams.

Foster said the previous incarnations of Super Rugby had struggled to engage fans because of the succession of weaker teams added over the years.

"This is not a charity. We've got to actually make sure they're feasible, they're financially viable and the public are going to really get in behind them," Foster told NewsHub.

"It's got to be competitive, it's got to be financially viable.

"We've seen in the past that if you let in teams that actually can't survive, then you've got to keep changing the competition around."

Foster's thoughts were echoed by former All Blacks greats Mils Muliaina and Sir John Kirwan.

On New Zealand's Sky TV, the pair advocated for a nine-team competition, featuring three from Australia and one from the Pacific. Muliaina said a fourth Australian team could be added if it could be justified by player strength and a strong bottom line.

The speculation has sparked a rift in trans-Tasman relations, which have been described by RA chairman Hamish McLennan as increasingly "master-servant" in nature.

McLennan's description won't have dimmed following the comments of Foster, who pointed to New Zealand's historical dominance of Super Rugby.

"We've got to do whatever we can to get competitive teams against our teams," Foster said.

"We're pretty secure in our five so once they (Australia) get their number, I guess we sit around and have a conversation."

- Daniel Gilhooly