Coiba is home to animal, plant and bird species found nowhere else in the world.

The bill, which is being debated this week, could become law by mid-June, legislators say.

Coiba is a national park by decree, but not by law.

The proposal would allow logging, hunting and fishing on the island with appropriate permits, going against a proposal vetoed by President Mireya Moscoso a year ago that banned commercial activities on the Pacific island.

"This bill is seen as a speculative move by the ministers involved," said Lider Sucre, director of Panama-based conservation group Ancon.

"The way to allow Coiba to survive is to promote low impact eco-tourism, not big hotels or allow logging of tropical hardwoods," said Todd Capson, a scientist and researcher at the Smithsonian Institution in Panama City.

Coiba is the largest primary forested island in the Americas, and hosts one of the last relics of tropical moist forest in the Central American Pacific.

Three hours from Panama's southeastern mainland, the 192 sq mile (493 sq km) island is also under consideration as a United Nations World Heritage Site.