Oil price worries
Italian oil group Eni chief Mr Descalzi called for Opec to cut production.
He said: "Opec is like the central bank for oil which must give stability to the oil prices to be able to invest in a regular way."
Politicians, economists and industry leaders in Davos have been voicing their worries over the impact of lower prices.
Total and BHP Billiton both said on Wednesday that they would cut back on shale oil projects.
People's Bank of China governor Zhou Xiaochuan said low oil prices could slow down China's development of renewable energy projects.
He said: "We worry a little bit that the price signal may give disincentive for new energy types to develop and could reduce investment in new non-fossil energy,"
But he added that lower prices would be good for the economy and job creation, because China was dependent on imported oil and gas.