"We will be filing today. We are serving to the other party's attorneys, not the media," department spokeswoman Zingaphi Jakuja said.

"As far as I know, media are not applicants in the matter so we are under no obligation to furnish our affidavit to media."

In January, the High Court in Pretoria ordered Shabangu and Ramontja to respond by January 31 to an application by the Treasure Karoo Action Group (TKAG).

The TKAG wants details on an inter-departmental task team studying the impact and viability of fracking, or hydraulic fracturing, in the Karoo to extract natural gas.

TKAG chairman Jonathan Deal said: "There is a whole lot of secrecy... we want to know who is involved, what are their qualifications, what is their brief, what scientific evidence are they using."

It was especially important to look at what evidence the team was looking at as fracking "had creeped into South Africa on the back of industry-based reports".

Fracking involves injecting, under high pressure, a mixture of chemicals and water into the earth, to free natural gas. The exploration programme, proposed by oil company Shell, has been criticised by environmental groups who claim it will harm the sensitive Karoo environment and poison underground water.