"The private sector is hoarding close to R1.2 trillion in uninvested cash," Vavi told delegates at the Congress of SA Trade Unions' (Cosatu) 11th national congress in Midrand, Johannesburg.

"This is social surplus which workers have produced, and which business are refusing to invest productively."

Vavi was delivering the Cosatu political report on the second day of the conference.

A weakness of the federation was that there were no campaigns to combat capitalism, because of differing ideas which caused fights amongst the affiliates.

"Where is the Cosatu march to the JSE [Johannesburg Stock Exchange] to say please invest this money... We want to work with you to make sure you invest," said Vavi.

"Where are these campaigns?"

He said macro-economic policy remained at the heart of many disagreements on the economy.