Top oil executives defended their record profits and called for the US to open up more fields for exploration at a heated congressional hearing on Wednesday that reflected increasing political pressure on lawmakers to tackle the rising cost of petrol.

As the price of crude oil broke through $133 per barrel, Stephen Simon, senior vice-president of Exxon­Mobil, the biggest US oil company, told the Senate judiciary committee: “Our profitability in absolute terms is large but must be viewed in the context of the massive scale of our industry and our dependence on high earnings in the current up cycle to sustain the huge investments required over the long term.”