Ecuador's government has issued an environmental permit for oil drilling in the pristine Amazon reserve that President Rafael Correa initially offered to exempt from exploration if rich countries would pay his government.

Correa abandoned that effort last year due to insufficient interest and has spurned pleas by environmentalists to spare the Yasuni reserve.

Earlier this month, Ecuador's electoral council declared invalid a petition drive seeking to prevent drilling in the 6,500-square-mile Amazon reserve.

Environment Minister Lorena Tapia said on state television that with Thursday's signing of the permit camps and access roads can now be built. Production could begin as early as 2016.

Two indigenous groups living in voluntary isolation inhabit Yasuni, which the United Nations in 1989 declared a biosphere reserve.

The Associated Press