Deputy president Kgalema Motlanthe on Tuesday defended a carbon tax that seeks to "green" the South African economy.

"The introduction of carbon tax requires the availability of corresponding fuel quality to reduce greenhouse gas emissions into the atmosphere," Motlanthe said in his address to the oil and gas indaba held in Bloemfontein.

"Tightening of fuel specifications and standards is inevitable for compliance with environmental challenges and new vehicle engine technology requirements."

Motlanthe said the carbon tax would be accompanied by new guidelines for fuel efficiency to be published by the energy department.

The deputy president said an integrated energy plan for the country was no longer an option.

"Our strategic thrust should be that of ensuring... the security of energy supply."

The department wanted to, among others, partner with the industry operating in this sector to develop a 20-year plan for managing liquid fuels.

"It will encompass the whole liquid fuels value chain, including logistics."

Earlier, the department said the indaba would enable those in the oil and gas sector to deliberate on exploration and production and the development of the liquefied petroleum gas business.

The role of black-owned entrepreneurs in the sector would also be discussed.

Motlanthe said liquid fuels shortages in December 2005, as well as electricity blackouts in recent years had served as wake-up calls.

"A positive aspect to emerge out of the electricity and liquid fuels shortages is that they served to awaken us and to strengthen the resolve with which we address challenges of energy security."

Motlanthe said the government could not tackle these problems on its own and needed sustainable partnerships to ensure security of energy supply.

South Africa could not achieve the growth and development it aspired to without energy security.