The Prime Minister's official spokesperson was asked whether the PM was disappointed at the Office of Fair Trading's report into fuel prices.
She said it was for the OFT to look at the issue, adding that they have made it clear that if there is further evidence of alleged price fixing, they will look into it and take action.
But for now, the Department of Energy and Climate Change is considering its response to the OFT's report.
The Office of Fair Trading report found that, pre-tax, the UK has some of the cheapest road fuel prices in Europe.
The Office of Fair Trading said its investigation into the UK fuel market identified a lack of pricing information on motorways as a concern and it not rule out taking action in some local markets if there was "persuasive evidence of anti-competitive behaviour".
In August 2012, prices were on average 7.5ppl higher for petrol and 8.3ppl higher for diesel than at other UK forecourts.
Competition is "working well" in the UK road fuel market and rises in pump prices over the past decade are largely due to increases in tax and the cost of crude oil, according to an Office of Fair Trading report.
It found "very limited evidence" that pump prices rise quickly when the wholesale price goes up but fall more slowly when it drops.
According to the AA's January fuel report, petrol prices are back on the rise after three and a half months of gradual falls.
It found that the price gap between petrol and diesel has widened from 5p in the summer to 8p this winter.
According to the AA's fuel report in December 2012, throughout the year the cost of petrol in the UK averaged 136.40p a litre and diesel 142.48p.
Previous average pump prices across a year were:
- 2012: petrol 136.40p, diesel 142.48p
- 2011: petrol 133.65p, diesel 138.94p
- 2010: petrol 117.24p, diesel 119.60p
- 2009: petrol 100.02p, diesel 104.38p
Different costs make up the price of petrol at the pump, for example at 130p per litre:
- The actual cost of fuel would be around 48p
- The retailer gets about 5p
- 80p goes on tax and VAT
Later today the Office of Fair Trading will release their findings into whether reductions in the price of oil are being passed on to motorists.