Labour leader Ed Miliband said consumer groups would be given a greater role in identifying and fixing "broken markets" if his party won the next General Election.
Mr Miliband told BBC1's Andrew Marr Show he would legislate to ensure Which? and Citizens Advice would be given a say in setting the agenda of the Competition and Markets Authority.
He claimed Labour would be "the party of the consumer" and the plan for an annual competition audit of the economy would help ensure that areas where regulators were failing would be identified and tackled.
The Labour leader said: "Unless you bring the consumer into the heart of these things, we are not going to get the change we need, we are not going to get the change we need, we are not going to shine the light on these broken markets."
He added: "The Competition and Markets Authority scrutinises competition across the board. They will be working with Which?, the CAB and others to say 'where are the areas where competition isn't working, what are your members telling you about where we need to act?'
"They will be sending a report to Parliament and it will be framing the work for the year ahead."