Conservative MP Robert Halfon said the price of petrol at the pumps has risen by a "huge amount" since 2009.
Speaking to Daybreak he said he warned that petrol price fixing had gone on "a year ago".
He added: "We had a whistleblower approach us, we urged the office of fair trading to do a full investigation, they did a partial Sir Humphry investigation, and we say enough is enough."
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