Gas exporting countries, grappling with collapsed global markets, on Friday called for a "fair price" for the commodity after a summit in Bolivia.

The Gas Exporting Countries Forum seeks a "fair price for natural gas," taking into account its environmental benefits and energy efficiency, a declaration said.

The price of natural gas is linked to that of petroleum and its derivatives, and is down roughly 50 percent from peaks of three years ago -- partly from rising shale gas production in the United States, which does not belong to the Forum.