Unions are threatening to strike until the South African Broadcasting Corporation (SABC) addresses their concerns, including doing away with retrenchments.

The Communications Workers Union (CWU) said on Sunday it will "shut down the corporation".

CWU secretary general Aubrey Tshabalala said during a recent picket at the SABC headquarters in Auckland Park, Johannesburg, that the broadcaster was given until Friday to respond to grievances the unions have handed over to SABC management, but they had received no response.

"I have checked my emails, and there has been no revert... we will now receive a mandate from the workers on what should happen next", Tshabalala told News24.

"A total shutdown is on the cards, however the continuation of a broader consultation is unfolding. We want to involve society at large since this is a matter of public interest," Tshabalala added.

SABC spokesperson Neo Momodu told News24 on Sunday night that the broadcaster "takes the demands by the unions seriously" and it will respond to them as soon as the consultation processes with the stakeholders are concluded.

"Some demands require intense consultations with key stakeholders, which are still underway".

He said that once consultations have been concluded, a clear process will then be mapped out with regards to a plan of action.

Almost a thousand permanent staffers stand to lose their jobs if the retrenchments go ahead, with over 1 200 freelancers also expected to be laid off.

The public broadcaster has already warned that it would not be able to pay salaries by March next year if it does not retrench staff.

Unions demand a new funding model for the broadcaster.

Salaries at the SABC amount to almost 50% of its total revenue, leaving less money for operational costs.

It has previously said that in order for it to be financially viable once more, it needed to decrease its salary payments, and engage in what it has termed "much needed restructuring".