The situation threatens to turn ugly just two weeks out from the start of the revised season.

Professional Rugby League Match Officials on Thursday claimed the league had no right to change the officiating model under the current enterprise agreement.

They have engaged the services of Harmers Workplace Lawyers with the goal of finding a resolution before the competition resumes on May 28, but won't rule out strike action.

V'landys has launched a passionate defence of the decision, saying PRLMO chair Silvio Del Vecchio is not helping referees.

"It's totally ludicrous and I don't think his confrontational and misleading approach is helping his association," V'landys said.

"We've done nothing wrong. All the 21 referees that are full-time will be kept."

Del Vecchio told AAP they are confident of getting the NRL to overturn Wednesday's decision and go back to using two on-field referees.

The PRLMO says that under the terms of the four-year agreement, which began in 2019, the governing body must persist with the two-referee system.

In a letter sent to the ARL Commission the union presented a number of reasons why any rule change required more consultation.

They included duty of care to players and match officials, best interests of fans and sponsors, and potential errors in calculation of financial savings.

Cost saving has been a reason given by V'landys to move back to one referee, while he also says it has the backing of fans.

The NRL points to a survey conducted in 2019, where fans were asked what rule innovation would they like to see to make the game more unpredictable and entertaining.

Around 18,000 people responded, and V'landys says the second highest response behind changes to scrums was reverting to one referee.

AAP has requested a copy of the survey results.

Del Vecchio calculated that even if the NRL terminated all eight of its casual whistleblowers, the savings amounts to less than $300,000 a year.

"We've done the maths. When you average it out over the course of the remaining games of the year, it equates to $20 per minute of each game," he said.

"It's just peanuts. It's unnecessary.

"More importantly, they haven't consulted with us. We can recommend different ways to save a lot of money in the NRL in the refereeing department."

The NRL claim referees were briefed on the changes last week, and that union representatives were present at a consultation meeting on Monday.

A submission from the PRLMO is also understood to have been presented to the ARL Commission prior to its final decision.

The referees union says the league has often previously preached about the "superiority" of the two-referee model, as recently as last year's grand final.

Del Vecchio went on to claim that more than 80 per cent of play-the-ball infringements and illegal tackles are called by the pocket (second) referee.

Asked whether the referees would take strike action if a resolution can't be reached before May 28, Del Vecchio said: "We'll assess it at that time."

Australian Associated Press