The Government has been urged to launch an inquiry into petrol pricing as motorists continue to face "significant" regional differences in price.
Iain McKenzie, Labour MP for Inverclyde in Scotland, says petrol and diesel prices in his constituency vary by as much as 3p or 4p depending on which forecourt drivers use.
He said many independent fuel retailers have had to close in recent years because large supermarkets such as Tesco and Asda have come to dominate the market, effectively ending competition in many areas.
Mr McKenzie said fuel tax and the supply chain - and where investments are being made - are further factors which negatively influence the price of fuel.
He called on Transport Minister Patrick McLoughlin to back the Labour party's demand for an inquiry by the Competition and Markets Authority into the issue, saying drivers should enjoy the same level of protection from supermarket dominance as dairy farmers.
Copyright Press Association 2015