Government officials are working with SkyCity to close a massive funding gap in its plans for a new Auckland convention centre.

The casino operator says "design improvements" have seen the cost revised up from 402 million dollars, to up to 530 million.

It wants taxpayer help to close the gap, but the government's not committing.

A spokeswoman for Minister Steven Joyce says officials are working with the company on options to reduce the cost.

She says they're also exploring other ways the costs could be met.