Important decisions about the rebuild of Dunedin hospital should not take place behind closed doors, says mayor Dave Cull.
A government group has begun the process to design a replacement hospital, expected to be built for about $300 million within the next decade.
Initial reports have signalled the need for changes to hospital services, although details have not been released.
Mr Cull has sent letters to three government ministers, saying he was very concerned at the level of uncertainty being created.
"Various reports or commenatries have come out, various people have spoken about it, and yet there hasn't been any reassurance from anybody that they've got it under control. There's been nothing, nothing has been decided yet. I'm not comfortable when we don't get assurances that we are going to be involved early enough."
Mr Cull said he feared decisions could be made behind closed doors, and that they could be bad for the city and Otago University's medical school.
He said no-one would give assurances that city and university leaders would be involved early enough in the redesign process to avoid important decisions being made behind closed doors.
A spokesperson for the health minister, Dr Coleman, said he could not comment because he was travelling to the Rio Olympics.