Auckland Mayor Len Brown will be censured by his councillors, who disapprove of his failure to declare nearly $40,000 of free and upgraded hotel rooms.
Councillors met for five-and-a-half hours on Monday to discuss their response to a review which found the mayor had not complied with the council code of conduct.
Mr Brown attended the first 90 minutes of the closed-door meeting, offering a full apology and acknowledging he needed to rebuild their trust in him.
At a media conference later, deputy mayor Penny Hulse said not all of what was discussed would be revealed before an open council meeting on Thursday. However, Mr Brown would be censured at the meeting.
"I think it's clear that the motion of censure, whilst to many of the public it might feel like a slap on the wrist with a wet bus ticket, it is ... a serious action that we do not take lightly," Ms Hulse said.
"However, there are other issues that we'll work through with the mayor that are of consequence."
That included whether Mr Brown would contribute to the $100,000 cost of an auditor's review, sparked by the mayor's two-year extra-marital affair. The Ernst & Young review uncovered his failure to declare the rooms as required in the council code of conduct.
It found he had accepted nine complementary hotel rooms and 64 upgrades, including three free rooms at SkyCity - none of which were declared as gifts as required.
The mayor had previously said he would not resign following the review, and there are no specified penalties for breaching the code.
He said after the meeting he had been humbled by it but did not accept there were grounds for him to meet part of the cost of the review.
Mr Brown said he had had messages of support but also had to "cop" criticism.
"I accept that I erred and so having made an unreserved apology, I've got to cop what comes at me and so I'm doing that."
Ms Hulse said councillors were united in their view and disappointed in Mr Brown's conduct.
"The governing body makes no secret of the fact that we express our profound disappointment and disapproval of the mayor's actions with regard to his conduct and undeclared conflicts of interest, and the damage to Auckland's reputation," she said.
"And (it is) also acknowledging the disappointment that our communities have expressed."
Councillor George Wood said some people might think the council censure would not do much but he disagreed.
"I think it puts on the record the council disdain in what has happened. I think it indicates in a very formal way our concern and it goes on the record that we have these very serious concerns in relation to the way that he's conducted himself over the last three years," Mr Wood said.
However, he did not believe believe Mr Brown's actions warranted his being asked to step down as mayor.
Councillor Dick Quax, who opposes Mr Brown, earlier said the mayor could not hope to do his job because he was hopelessly compromised and should step down.
"Anybody else in a similar position in the private sector would say 'look I can't do my job, I'm out of here' and the mayor should do the same."