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By Stephanie Kelly

NEW YORK, Sept 7 (Reuters) - Natural gas prices have surged not because of a lack of supply but due to a lack of infrastructure, as global demand for U.S. liquified natural gas increases, the chief executive of Williams Companies Inc said on Wednesday.

Exports of liquified natural gas should not be restricted because the United States has plenty of supply, CEO Alan Armstrong said at the Barclays CEO Energy-Power Conference.

Natural gas supply, particularly in the Haynesville region, is growing, he added.

"The Haynesville growth is really surprising us and I think by the end of the year it's going to surprise a lot of people how fast gas supplies have grown in the Haynesville and that's not going to be stopping any time soon," Armstrong said.

Williams is especially focused on natural gas supply growth in the Marcellus, Utica and Haynesville regions, Armstrong said. (Reporting by Stephanie Kelly Editing by Bernadette Baum)