Botswana's government Tuesday said environmental protection was key in its search for natural gas, rejecting claims that fracking was already under way in the country's top wildlife park.

"There are currently no fracking operations going on in the country except exploration drilling by various exploration companies," said a statement from the Ministry of Minerals, Energy and Water Resources.

This week, the Open Society Initiative for Southern African (OSISA) said Botswana had granted concessions "over vast tracts of land" while keeping the public in the dark about the developments.

"There is coal bed methane prospecting in the reserve as well as other areas of Botswana, but no commercial operations now or in the near future," government spokesman Jeff Ramsay said.

"We are guided by environmental regulations that we adhere to," he said, dismissing reports that the Central Kalahari Game Reserve was threatened by mining activity.

Fracking, or hydraulic fracturing, has met with intense resistance from environmental groups in countries such as the United States who say the process damages the environment.

The 52,800 square kilometre (20,400 square mile) Kalahari park is also home to the indigenous San people, who have faced several attempts by the authorities to remove them from the park.

OSISA had voiced concern that fracking would lead to devastating results for the water scarce country, as well as for the San.

The organisation also revealed that the government had granted coal bed methane concessions within Chobe National Park in the north. South Africa's Sasol, Australian-based Tamboran Resources and Anglo American are said to be among companies granted drilling licences.

The rush for natural gas has been seen as a growth-boosting alternative by countries seeking investment.

Botswana's diamond-led economy had seen a slump due to slow export earnings.

Neighbouring South Africa recently published regulations for fracturing, earmarked for the arid Karoo region, a year after lifting a moratorium on the process.