KwaZulu-Natal Premier Zweli Mkhize condemned artists who used their work to insult the leadership of the ANC in the name of freedom.

"We must not allow people to abuse our freedom, people who will go around and in the name of art want to start insulting our leaders, we can not have that," Mkhize said on Sunday in Durban.

He was speaking at the National Union of Metalworkers of SA (Numsa) rally to celebrate the union's 25th anniversary.

Mkhize was referring the controversial painting "The Spear" by artist Brett Murray which showed President Jacob Zuma with his genitals exposed.

"We must make sure we understand that this will strengthen our contribution to ensuring that this revolution is not diverted by people who are wishing for the good old days of apartheid. Such as FW de Klerk who speaks about how good it was in the days of Bantustan which means he is taking the reconciliation for granted," Mkhize said.

He said those who fought for freedom in this country had made many sacrifices.

"We must not allow those who administered the apartheid to go back and start expecting us to support the notion that apartheid was better than where we are today. The march by DA, it should never be allowed that somebody must march against the organisation because they disagree with the organisation," Mkhize said.

Congress of SA Trade Unions, secretary general Zwelinzima Vavi said the fight for the banning of labour brokers was not over.

He said the union spoke to Zuma when it had its march on 7 March and it was waiting for a response.

"We are tired of voting and seeing no change in the workplace. We want freedom to make a difference, we want labour brokers to be banned," Vavi said.