About 1.3 million public servants who've been on strike for 20 days have agreed to go back to work while negotiations over a final settlement continue.

The unions involved in the strike say there are three weeks to 'finalise consultation' on the draft agreement .

The strike has seen massive intimidation of nurses and teachers which resulted in a number of deaths and matric prelim exams being postponed in some provinces.

The 20-day strike also strained President Jacob Zuma's ties with leftist allies who helped propel him to power, intensifying debate on jobs and economic policy.

During the shutdown Cosatu secretary general Zwelinzima Vavi told a union meeting: "Of course the strike is political. It is workers making political statements."

"Two years after Polokwane, we have nothing to celebrate. We lost more than 1.1 million jobs. As a result, 5.5 million South Africans have been pushed into poverty."

One economist put the cost of the strike to the economy at R1 billion per day.