"I have learned a valuable lesson over the past 24 hours about the power of my words," Mr Radich said yesterday.
"To be clear - a racist comment is always a racist comment. It is never a minor thing."
His statement - and an unequivocal apology - followed ill-considered remarks he made in an RNZ interview on Wednesday, when he discussed the Dunedin City Council’s censure of Strath Taieri Community Board chairman Barry Williams.
The council has asked Mr Williams to consider resigning as board chairman after he was found to have materially breached the code of conduct relating to a comment made to a member of the public.
"It happened in a pub and he didn’t even remember that it had happened, so it was just a relatively minor thing," Mr Radich had told RNZ.
The mayor clarified he was appalled and disappointed by Mr Williams’ comment.
"I have reflected on this ... and I want to apologise unreservedly for minimising the clearly racist comment made by the chair of the Strath Taieri Community Board in my comments to media.
"My hope remains that the chair will reflect on his position and his use of language."
Mr Radich’s own use of language was under scrutiny yesterday.
As of yesterday afternoon, no complaint had been filed about the possibility the mayor breached the code of conduct.
Mr Radich had earlier eased the pressure by telling the Otago Daily Times he had not intended to trivialise a racial slur and he was "sorry for creating a misconception".
Longtime city councillor David Benson-Pope said the mayor had read a report by an investigator and knew precisely what Mr Williams had said.
"There was no doubt about how offensive the statement was.
"How could the mayor possibly trivialise it afterwards?
"It really does raise serious questions about the mayor’s competence.
"He has shown a complete lack of judgement."
Cr Benson-Pope said Mr Radich had previously made a series of gaffes.
They have included putting a positive spin on design cuts to the planned new Dunedin hospital and "misspeaking" about sea-level rise.
University of Technology Sydney’s local government scholar Andy Asquith said Mr Radich had damaged the reputation of the office of mayor and he should consider his own position.
Dr Asquith said "misspeaking" was an excuse trotted out too easily by politicians.
"Sometimes it’s just best to keep your mouth shut."
Deputy mayor Sophie Barker said it was "a very challenging situation".
The council had done all it could to call out unacceptable conduct by Mr Williams, she said.
The racial slur was "completely and utterly unacceptable", Cr Barker said.
Cr Barker said all elected representatives had a duty to be mindful of their responsibilities.
Cr Jim O’Malley said the conduct of Mr Williams had to be met with the strongest response available.
"Mr Williams should consider resigning," Cr O’Malley said.
"I don’t know why the mayor said what he said."
Cr Andrew Whiley said he was "not going to put my boot in" against Mr Radich through the media.
He later added: "I am disappointed by the mayor’s comments in the radio interview and I have shared my views concerning this directly with the mayor.
"I strongly support the mayor in how he is leading the city."
Cr Carmen Houlahan said she did not "see any benefit in bringing this up again, as the mayor apologised".