RA chairman Hamish McLennan dropped a bombshell last week by reportedly telling Kiwi counterpart Stewart Mitchell that Australia would consider going it alone in Super Rugby from 2024 onwards.
McLennan said in a later interview that RA would fulfil its 2023 Super Rugby Pacific commitments but hinted an all-Australian competition could be launched after that, with a view to the Rugby World Cup in 2027.
Rennie is adamant the model that will benefit the Wallabies the most is the current one, in which Australian sides battle the might of New Zealand's best.
"I think it's good for both countries that we play Trans-Tasman footy," Rennie said.
"I think the competition has been excellent this year, and our sides have been more competitive. I think it's good for them, it's good for us. I'd like to see that continue.
"They've got some of the best players In the world. You want to be playing the best players. That's how we will get better and be challenged, so it's important."
Some observers believe McLennan's threats have been made merely in a bid to secure a larger slice of broadcasting revenue.
New Zealand Rugby is believed to collect more than $90 million from the current broadcast deal, roughly three times what RA receives.
"I understand Hamish is an innovative thinker. From a commercial point of view, (Rugby Australia) want a bigger slice of the pie. So I understand his thinking," Rennie said.
"But I think what a lot of New Zealand clubs will think, too, is that us playing Trans-Tasman games are good for us. We've just got to make sure financially it's beneficial as well."
The Wallabies are currently in camp on the Sunshine Coast to prepare for the three-test series against England which kicks off in Perth on July 2.