Oil crisis not over: warnings of diesel over $4 a litre

Some economists have projected big increases in fuel costs as countries run down their stockpiles. (George Chan/AAP PHOTOS)

Diesel prices could surge above $4 a litre in coming months under a scenario modelled by economists at National Australia Bank, potentially spelling a much more severe economic fallout than forecast by the Reserve Bank.

Fears of service stations running dry are a distant memory and petrol prices are back under the $2 a litre mark following government efforts to secure additional supplies to Australia.