Folau was sacked for a high-level code breach for a religiously-motivated social media post which said hell awaits homosexuals, among others, after he had previously been warned following a similar post last year.
"RUPA appreciates the difficult position which this incident has placed on Israel's teammates and the broader professional playing group, and we will continue to support each RUPA member," it said.
"RUPA remains proud of its diverse playing group and is committed to empowering and supporting each of its members to have conviction to express their faith and beliefs confidently.
"Clearly, there remains a great deal of work to be done in relation to this subject, but what remains paramount and a non-negotiable is empowering all of RUPA's members to feel confident in understanding their rights and their responsibilities when expressing their faith and beliefs."
Seriously 🤦♂️🤦♂️ Might as well sack me and all the other Pacific Islands rugby players around the world because we...
Posted by Taniela "Tongan Thor " Tupou on Tuesday, 30 April 2019
It comes after Folau's teammate and Wallabies star Taniela Tupou also posted on social media
"Seriously ... Might as well sack me and all the other Pacific Islands rugby players around the world because we have the same Christian beliefs," Tupou posted late on Tuesday night.
"I will never apologise for my faith and what I believe in, religion had nothing to do with rugby anyways... #TYJ"
He was joined by fellow Wallaby Samu Kerevi in making a bold public stand for their Christian faith.
The backlash sparked fears Rugby Australia could face a Polynesian player revolt in response to their action against Folau.
RUPA's call for an unprecedented review is a first step in an attempt to heal the divide.