Fuel duty is due to increase again by 3p litre on August 1, the AA has warned.
June's AA Fuel Price Report shows that, since mid-May, average UK petrol prices have fallen 4.63p a litre, from 138.40 to 133.77.
This is on top of the 4.08p-a-litre fall the previous month and is the biggest monthly drop since the petrol price dived 5.4p a litre between mid-November and mid-December 2008.
Even so, the overall 8.71p-a-litre reduction in the pump price petrol since the 142.48p record on April 16 is still short of where it should be, the motoring group said.
More top news
Chancellor George Osborne has announced a £500m investment for the Faslane naval base in Scotland, home of the UK's nuclear deterrent.
Five-times major winner Maria Sharapova has pulled out of the US Open tennis championships due to a leg injury.
Police are hunting for a mother who has disappeared with her 10-week-old baby.