The average cost of a litre of petrol at UK forecourts on Tuesday was 167.6p according to data from Experian Catalist.
The Competition and Markets Authority (CMA) warned that retailers could be fined if it launches a formal investigation into the sector.
The previous record price for petrol of 167.3p per litre was set on March 22, the day before a 5p cut in fuel duty was implemented by Chancellor Rishi Sunak.
Diesel prices have also climbed to new highs, reaching an average of 180.9p per litre on Tuesday.
That was the same day Business Secretary Kwasi Kwarteng wrote to fuel retailers “to remind them of their responsibilities” amid claims they had hiked profits following the reduction in duty.
RAC analysis found retailers’ average profit margins for a litre of petrol and diesel are currently 11p and 8p respectively. In the month up to the 5p per litre duty cut on March 23, it was 9p for petrol and 6p for diesel.
RAC fuel spokesman Simon Williams said filling a typical 55-litre family car with petrol costs an average of £92.53, while the bill for a diesel car is “teetering on the brink of £100” at £99.55.
He went on: “So far in May, a litre of unleaded has rocketed by more than 5p a litre and diesel by 3.5p.
“Since the start of the year it’s a far bleaker picture as petrol is 22.5p higher and diesel an astronomic 32.0p."
With the prices continuing to soar, here are the cheapest places to fill up in the region:
Tesco Wolverhampton, Penn Road - unleaded: 158.9p, diesel: 173.9p
Asda Wolverhampton, Jack Haywood Way - unleaded: 159.7p, diesel: 172.7p
Sainsburys Wolverhampton, Raglan Street - unleaded: 159.9p, diesel: 173.9p
Asda Tipton, Wednesbury Oak Road - unleaded: 160.7p, diesel: 174.7p
Asda Great Bridge, Brickhouse Lane South - unleaded: 160.7p, diesel: 174.7p
Asda Oldbury, Wolverhampton Road - unleaded: 160.7p, diesel: 174.7p
Sainsburys Oldbury, Freeth Street - unleaded: 160.9p, diesel: 174.9p
Tesco West Bromwich, Reform Street - unleaded: 160.9p, diesel: 174.9p
Sainsburys Blackheath, Halesown Street - unleaded: 160.9p, diesel: 176.9p