U.S. utilities have withdrawn a record amount of natural gas from underground storage to meet heating and power needs during an extremely cold winter, but gas producers say they are confident they can rebuild inventory. "We believe North America has the capacity to supply far more natural gas than we are doing now at a reasonable price," said William Maloney, Statoil's executive vice president of development and production for North America, speaking at the IHS CERAWeek conference in Houston, an annual meeting of global energy leaders. Some traders have expressed doubts that inventories would be rebuilt in time for next winter, but Maloney said the biggest challenge is not supply, but demand.