Dunedin Mayor Dave Cull has called out Mondelez for refusing to take up the city council's offer to discuss options for keeping the Cadbury factory open.
About 200 people braved a chilly morning to attend a rally this morning in the Octagon to urge a change of heart from Mondelez.
In his strongest public comments yet on the closure threat, Cull told the rally he was disappointed with the lack of response from the multinational.
"I along with other city leaders have met with representatives of Mondelez and . . . asked them under what conditions would they possibly retain the factory in Dunedin.
"Disappointingly, they have not been forthcoming with a response, insisting that they complete consultation with their workforce before looking at other possibilities.''
However, Cull said Mondelez had told him there was nothing more the council could have done to support its presence in Dunedin.
He urged them to reconsider the city's invite to work together to find a solution, perhaps retaining part of the factory.
"They are wrong to underestimate and even devalue the contribution of this city to their success.'' Cull said Mondelez would be "incredibly misguided'' to close the "efficient and profitable'' factory and lay off the "top performing'' workforce.
"If Mondelez goes ahead with its proposal and closes the factory than it will ultimately regret the decision,'' Cull said.
It was "beyond belief'' that Mondelez would consider leaving Dunedin, where its operation had performed so successfully, he said.
Cull said the closure was not, as some had claimed, a "foregone conclusion''.
Green Party co-leader Metiria Turei said Dunedin had been caught in Mondelez's worldwide cost-cutting drive, which had seen it lay off thousands of workers.
Dunedin had added "massive value'' to the Cadbury brand, she said.
"It was Dunedin that made Cadbury successful in this country.''
The city must fight back to avoid being a "victim'' of a corporate-driven attitude, Ms Turei said.
Dave Kearns, a former Hillside worker laid off when the Dunedin rail workshop closed in 2012, told the rally that while the campaign to save Hillside failed, it had been worthwhile.
Kearns said the campaign built political awareness about outsourcing.
Kearns said today's rally was just the start of a bigger effort to save the factory.
"This is going to get bigger and better,'' he said.
Labour Dunedin South MP Clare Curran said the Hillside closure demonstrated the perils of losing New Zealand-based manufacturing, as the trains sourced from China had been "asbestos ridden''.
She said Kiwi confectionery brands "must not be taken offshore'' for manufacture.
Curran challenged the National-led Government for its perceived lack of action over Cadbury.
"Where were you? What did you know?'' Curran said.
Dunedin North MP David Clark, city councillor Damian Newell, union supporter Roger Tobin, E tu organiser Neville Donaldson, Cadbury worker Donna Bouma, and event organiser Don Pryde also spoke.
In a light-hearted gesture at the end, Pryde invited children to the front for a lolly scramble with Cadbury Favourites.
Last month, Mondelez told workers it planned to close the Dunedin factory by March 2018 and lay off more than 360 workers.