The International Rugby Board has ruled it has no jurisdiction to intervene in the player release row between the Welsh Rugby Union and its regions.
That has prompted the WRU to make a new request to the regions to honour what it calls "contractual obligations".
Acting for the regions as head of Regional Rugby Wales, ex-WRU boss David Moffett then fanned the flames, saying:
"To get a mealy-mouthed statement from the WRU press office is a disgrace... the WRU's silence has been deafening."
The Union wants the players available 13 days before Wales' first autumn Test with South Africa on 8 November.
The four Welsh regions - Cardiff Blues, Newport Gwent Dragons, Ospreys and Scarlets - argue that will deprive them of their leading players for the last round of EDF Cup matches.
The IRB says the dispute is of a "private contractual nature", but has offered to help mediate between the sides.
RRW had already told the WRU a move to force player release was not "legally enforceable", prompting the union to seek an IRB ruling.
But on Thursday, world rugby's governing body decided the row was: "An internal domestic dispute between a Union and its constituents in respect of the scope, terms and/or application of a private contractual arrangement governing player release."
After that announcement the WRU issued a statement calling for the regions to "honour their contractual obligations and release all Wales international squad players for training from Monday 27th October."
In response, Moffett issued a strongly-worded statement saying: "Roger Lewis needs to step up to the plate and start acting like a chief executive so we can agree a way out of this, otherwise he needs to get out of the way so we can get this thing dealt with quickly by someone else at the WRU."
But Lewis later told BBC Wales he had been talking to the regions up until the end of last week and he had a 100-plus page draft participation agreement ready to hand over to the regions.
"A dignified silence is the most appropriate response (to the criticisms)," Lewis told BBC Wales.
"The most important thing to address here is the future of Welsh rugby and to behave in a way that maintains the dignity and the reputation Welsh rugby in Wales and outside," he added.
"We are far too busy working getting the job done and that is to get these documents back to the four regions based on months and months of work.
"Now is not the time to trade insults with each other, we need to rise above that.
"I'm far too focused on not thinking about what has been said about myself and the WRU. Rather, I'm focused on getting a document in place that will take the game forward."
Earlier this week Wales coach Warren Gatland said he was "despondent" over the row and believed that five days was not enough time to prepare for a Test properly.
The IRB's guidelines say each union should decide when players should be released and does not give a time frame.
Ex-WRU chief David Moffett now represents the Welsh regions
But the 13-day period is covered in a participation agreement between the WRU and the four regions.
However, RRW - a body unveiled on Tuesday with ex-WRU chief executive Moffett at its helm - alleged the WRU failed to comply to the letter of that agreement by not advising the regions of their requirements at the start of the season.
BBC Sport Wales understands the WRU disputes this version of events and maintains Gatland informed the regions of his player release needs in August.
Negotiations are under way on the new participation agreement referred to by Lewis.
It contains 14 main points designed to improve the game in Wales, with two of the most important concerning player release for internationals and player insurance.
The WRU and its four regions have been holding formal discussions over the terms of the new participation agreement since 2007.