Nelson ratepayers will have to fork out several hundred thousand dollars more, on top of the millions already set aside, to improve the city's main civic venue.
The council has approved a further $700,000 to redevelop Rutherford Park next to the Trafalgar Centre, currently being rebuilt to meet new earthquake standards.
Councillors voted to go ahead with the unbudgeted expenditure for what is now a $3 million Rutherford Park improvement project.
Mayor Rachel Reese said it was part of a large-scale urban improvement package linking the city to the sea.