Although many pumps will already have been selling fuel at that level or higher for several days, this is the first time in over a year the overall average has nudged above the threshold. The price of diesel rose to 116.88p.
The push has been driven by the weak pound to dollar exchange rate and a rise in oil prices that pushed the physical price of the black stuff above $50 a barrel for four days at the beginning of the month.
Oil prices lifted after Opec (the Organisation of the Petroleum Exporting Countries), a consortium of the world's biggest oil producing countries, provisionally agreed to curb oil output by around 700,000 barrels a day at the end of September.
The agreement, which is due to be finalised at a meeting in Vienna next month, would set daily production to between 32.5m and 33.0m barrels a day.
UK petrol prices slipped below 115p last August, in what motorists hoped would be a respite from sky-high fuel costs.