ANC president Jacob Zuma said he had never acted "unconstitutionally" and denied the ruling party was on a collision course with the judiciary, Business Day reported on Thursday.

SA was also not heading for a constitutional crisis, he said.

Zuma’s comments, made during an interview with Business Day on Wednesday, came as former ANC national executive committee member Kader Asmal initiated a petition and a campaign aimed at supporting the Constitution.

Asmal, a former cabinet minister, said that the values enshrined in the Constitution had to be protected and that a human rights culture needed to be deepened.

This came against the backdrop of allegations that Cape Judge President John Hlophe had tried to influence the Constitutional Court's decisions on cases involving Zuma.

Hlophe has in turn laid a counter-complaint with the Judicial Service Commission against the Constitutional Court. He accused it of prejudicing his rights by making its complaint against him public before the matter was put before the commission.

Opposition leader Helen Zille, who signed Asmal’s petition, challenged Zuma to sign the document as well.

Zuma said: "I have not spoken to Kader about his campaign. This is news to me. It is for the very first time that the opposition has joined hands with an ANC member on an issue."

Zuma also broke his silence over suggestions by some legal experts that his letter to the Constitutional Court, in which he asked when the court would rule on his cases, constituted a "threat" to the highest court in the land.

In the letter, Zuma’s attorney Michael Hulley warned on his behalf that the way the Constitutional Court handled its complaint against Hlophe would have consequences for "confidence" in the bench.

On his decision to write to the court, Zuma said: "The courts are there so we can all defend ourselves. I have done nothing unconstitutional. I am entitled to make such an inquiry because it affects me. I have a right like every other citizen to express my concern because it has a direct bearing on my matter."

Sapa