The Union has now opted for a preferred bidder to buy Cardiff, understood to be Ospreys owners Y11, which has added significantly to the uncertainty surrounding the region.
It has included Swansea council saying it would explore legal action, with leader Rob Stewart telling BBC Wales he is set to meet WRU officials.
“We’ve sought further conversations with them but haven’t had any,” he said.
“Interestingly the threat of legal action by the council has seen the chief executive of the WRU and the Ospreys coming to see us, so we’re interested to hear what they’ll say.
“It doesn’t take a legal genius to know that the process the WRU has followed has been one that hasn’t been as successfully managed as it could be.”
Stewart says the St Helen’s redevelopment was not at risk because of the Y11 proposals.
“We’ve been clear, the cabinet made a decision and it’s actually more than £5m we’ve set aside to help redevelop the ground,” said Stewart.
“It is conditional on the Ospreys being one of the regions chosen to be permanent as part of the WRU’s new arrangements.”
A decision on which sides will remain is still to be officially made, with Tierney saying the WRU hoped to avoid a tender process for the three licences available.