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.

Bolivian President Evo Morales, one of the last Latin American leftist leaders, said producers should combat "those who want to appropriate our resources through abusive price manipulation."