It was the intensity of the armed struggle, and not a decision by former president FW de Klerk, that led to Nelson Mandela's release 20 years ago, President Jacob Zuma said on Sunday.

Zuma, apparently rejuvenated by a break from his schedule in the wake of publicity over the birth of his 20th child, was addressing an ANC Boland region meeting in Paarl.

He said that among the things he would be likely to talk about on the 11th, the anniversary of the release and the date of his state of the nation address, was what it took for Mandela to "come out of prison".

"Don't be misled by people who might say today, we slept, we thought we must now release this man.

"No. It was the struggle, the intensity and depth of the struggle, that led to Madiba being released."

Today, in times of peace, everyone one is making claims about the release, even those who were on the opposite side of the liberation struggle, said Zuma.

'These are all our people'

"No, no. These are all our people. We led them. Because the ANC succeeded, they also succeeded."

The release, announced by De Klerk on 2 February 1990, will be commemorated on Thursday by an event at Groot Drakenstein prison near Paarl at which Mandela and Zuma will be present.

The prison, formerly Victor Verster, is where Mandela was held in the run-up to his release, a move that paved the way for a negotiated settlement and the first democratic elections in 1994.

"It looked like a dream that this man who had been in prison for 27 years was being released," Zuma said.

"So we must remember him and thank him that he has stayed with us up to now."

He said that after the commemoration and his state of the nation address, it would be "hard work".

He intended to make a number of commitments in the address, which for the first time ever was being delivered in the evening, so working South Africans could watch and listen.

"I want you to note down the commitments we are going to be making, so that you will be able to ask us, why are you not doing what you said you are going to do," he said.

"People must cook early and eat early, and sit there... so that the whole nation is part of the process."

Eyes on Western Cape

Zuma also used Sunday's speech to appeal for unity in the troubled ANC in the Western Cape.

Currently the province, the only one not controlled by the ANC, is being run by a task team appointed by ANC national.

Zuma said unity was the key to the ANC's success, according to Mandela, it was the rock on which the ANC was founded.

Every province, region and branch was equally important when it came to this.

"And therefore our focus should be to unite our organisation, not to do anything opposite to uniting.

"We must love one another as comrades."