National's leader has promised to repeal the proposed regional fuel tax if his party wins the next election.

Simon Bridges made the pledge in a speech to business leaders in Auckland this morning.

Bridges told Leighton Smith he'd overturn the tax because it's not necessary, and it will simply encourage more ill-discipline in spending by the government and councils.

He says if you manage the books right it's possible to deliver the infrastructure Auckland needs, without taxes.

LISTEN TO SIMON BRIDGES TALK WITH LEIGHTON SMITH ABOVE