A task team report on hydraulic fracturing (fracking) for shale gas in the Karoo will now be released in August.

Answering questions during Thursday's post-Cabinet media briefing, Cabinet spokesman Jimmy Manyi apologised for the delay, as the report should have been presented in July.

South Africa's large untapped shale gas resources - estimated to be the world's fifth-largest at 485-trillion cubic feet - under the ecologically sensitive Karoo cannot be explored to determine economic viability without using hydraulic fracturing (fracking), a controversial gas extraction method.

Mr Manyi said of the report: "The main problem is the recess that the Cabinet was on and this has impacted the release of the report," he said.

The Cabinet, the government's highest decision-making body, had a month-long recess and Mr Manyi said that during this time the ministers had attended to other matters.

He said: "An expectation had been created that the report would be released in July. However, the recess got in the way. The minister has assured me that the report would be released in the first cycle during August."

Three companies - Shell SA, Bundu Oil & Gas and Falcon Oil & Gas - have applied for permission to explore the ecologically sensitive Karoo region to test the viability of fracking for the gas deposits.

In April last year, the Cabinet placed a moratorium on shale gas extraction until a multidisciplinary task team had completed its report on the issue.