Plans to assess the impact of the decisions of the superior courts was not an attempt to undermine the independence of the judiciary, President Jacob Zuma said on Thursday.

"The courts, led by the Constitutional Court, through their judgments, continue to make an indelible mark in the transformation of society to realise the vision set out in the Constitution," he told the National Assembly in reply to points raised during debate on his state of the nation address.

The impact assessment would be undertaken this year.

"This assessment is with a view to reflect on the impact of the constitutional jurisprudence in the past 17 years of our democracy towards the realisation of the transformation goals envisaged by the Constitution," Zuma said.

The assessment would also focus on the role of the other arms of the state in giving effect to the court judgments.

"We reiterate that this exercise must not be viewed as an attempt by government to undermine the independence of the judiciary and the rule of law which are entrenched in our Constitution," Zuma said.

"It is in reality the enhancement of our constitutional democracy. We reaffirm our firm belief in the separation of powers and the independence of the judiciary and of all three arms of the state."

The assessment exercise fell within the mandate of the executive, "of formulating and reviewing policies of government", he said.

There was nothing unusual or untoward about it, he said.

Constitutions the world over were "dynamic and subject to review".

"In recognition of this fact, the Constitution provides that it must be reviewed at least annually by parliament, in terms of Section 45(1)(c). That is why there is the Constitutional review committee in Parliament.

"And therefore reviewing these matters is not a matter foreign to what our Constitution dictates. We are actually within our mandate," Zuma said.