Cr Gilbertson said the three regional councillors on the transitional board, Fenton Wilson, Alan Dick and Christine Scott, should resign from it to resolve perceived conflict of interest issues. The council's chief executive, Andrew Newman, who had moved over to chair the transitional board, should also resign, Gilbertson said: "There is a view from other councils that we are making a huge mistake and this will become an election issue ending with the dam falling over.
"The dam's all about getting the economy going but this is putting a big block in the middle of it which we need to deal with."
Regional council chairman Fenton Wilson said he had spoken to the mayors, Lawrence Yule and Barbara Arnott, about the letter and they agreed there was time to "remedy" the issues they raised.
Regional councillors would meet to discuss the letters and the mayors' views.
Councillor Neil Kirton, after the meeting, said the conflict of interest issue could be resolved by July: "We have asked that the investment company conduct a report which will demonstrate how it is going to handle the conflict of interest issues by July 31 this year and the council is going to do the same exercise."
Cr Kirton said all of the issues, including those around three councillors and chief executive being on the transitional board, should be "put on the table".