More than 150 coal ships are currently waiting to be loaded off Queensland and New South Wales ports.

“There has been an extraordinary expansion in coal exports and it does sometimes happen that the amount of coal to be exported runs ahead of the capacity of the ports to handle it,” Howard said.

“The problem in Newcastle, as I understand it, is a capacity problem and it involves responsibilities both on the part of the coal companies and also the State Government.

“I would like cooperation to work, we all would, but if cooperation doesn't work we have to look at some alternative.”

Hunter Valley coal producers and Port Waratah Coal Services have been working under a capacity balancing system since the interim approval earlier this year, but PWCS said yesterday it could take until late June 2007 to reduce the vessel queue to acceptable levels.

Queensland Resources Council chief executive Michael Roche said better planning is needed to fix the bottlenecks.

“If governments have got some answer, some solutions to contribute, that's good but we don't see those solutions lying in new or different regulation," Roche told ABC Radio.

Howard said the issue of port congestion will be discussed at the Council of Australian Governments (COAG) meeting tomorrow.