Touted as RA's next chairman, Wiggs had been pushing for the immediate installment of Australian Olympic Committee CEO Matt Carroll as departed chief executive Raelene Castle's replacement.

In an email exchange published by The Australian on Wednesday, McLean entertained Carroll's appointment.

However, citing a conflict of interest because of Wiggs' friendship with Carroll, McLean suggested Wiggs remain in a director role.

Instead he proposed incoming board member Hamish McLennan, a former Ten boss and News Corp senior executive, a more suitable chairman.

Fellow board members had also reportedly pushed back on the move that would have skipped any formal recruitment or interview process.

Supercars chairman Wiggs, credited for steering RA's player pay-cut deal during his brief RA posting, replied by saying what little regard he had for the board had "extinguished" and he would resign on Wednesday.

Confirming Wiggs had done just that, McLean said he "understood his reasons" for departing.

"He has undertaken some very important work and has made a valuable contribution to the organisation, in a very short time, and we are thankful for his contribution," McLean, who is also RA's acting chief executive, said.

"The immediate priority of the board is to install a replacement for Peter, and an interim chief executive."

It's another setback as the cash-strapped organisation navigates a way back to the field while trying to arrange a new broadcast deal.

It is hoped a domestic Super Rugby season could return in July, while a Bledisloe Cup series remains a prospect later this year.

But RA, awaiting rescue funds from World Rugby, faces a potential revenue hit of $120 million if no play is possible this year.

AAP