Importing and distributing natural gas to replace petroleum and other fuels is in the "public interest," with a timetable of six months being set to make the fuel available, the Costa Rican government said.

President Laura Chinchilla and Environment Minister Rene Castro signed an executive order Monday to speed up the importation of natural gas as part of a plan to make Costa Rica the world's first carbon neutral country by 2021.

Natural gas is "a transitional fuel toward fuels that are cleaner than those derived from petroleum for industry, transportation and business," Castro said.

"Natural gas is the cleanest and cheapest hydrocarbon, and it will help us in the transtion toward a really sustainable energy mix in the country," Castro said, adding that natural gas emits less CO2 than other fuels when burned.

Emissions of CO2 are believed to cause global warming.

Natural gas, according to Environment Ministry figures, is also cheaper than petroleum. EFE