Wellington, Sept 2 NZPA - Resigning BP managing director Peter Griffiths is warning that the petrol station business in this country is unsustainable.

Wellington-based Peter Griffiths said fuel prices would need to rise at least 10c a litre to start to make it profitable, The Dominion Post reported today.

The increase would include 5c for the oil companies at the wholesale level and another 5c a litre for independent station operators.

As a group, the big retail petrol companies in New Zealand made no profits in the past year, despite combined revenues of about $10 billion, Mr Griffiths said.

"It can't be sustained. We have competed ourselves to a point of collapse of all sorts of bits and pieces of the industry," he said.

Collapse was probably a strong word, but the profitability for wholesale operators was poor.

Companies Shell and Exxon Mobil were both looking at selling their petrol stations in this country.

BP stations are not for sale, but Mr Griffiths said its performance was bound to be "reviewed".