The market for driving instruction is crowded with part-timers looking to make a little extra income from their car, perhaps to defray the increasing cost of gas.

Mr Davies notes that, at current prices, a jump in prices of $20 a barrel would raise spending on oil by about 1 per cent of world spending on all products.

The announcement sent many motorists scrambling to fill their tanks during the hours before midnight, causing long lines before most gas stations around the country.