Former National Prosecuting Authority (NPA) boss Vusi Pikoli has closed the door on speculation that he might be returning to the post.

"I wish to thank all those who have confidence in me. The truth is that I have no intentions of going back to the NPA," his tweet read.

"I hope this closes the debate."

Pikoli was suspended from the position in 2007 by then president Thabo Mbeki. It was alleged that the decision stemmed from Pikoli's pursuit of then police commissioner Jackie Selebi.

Pikoli was eventually fired in 2009 by former president Kgalema Motlanthe.

The speculation about his return follows from the Constitutional Court's ruling on Monday that the appointment of Shaun Abrahams as NPA head was unconstitutional and invalid. When delivering his ruling in the apex court, Justice Mbuyiseli Madlanga said former president Jacob Zuma's decision to terminate Abrahams's predecessor Mxolisi Nxasana from the position as the National Director of Public Prosecutions (NDPP) was an abuse of power and that Abrahams was a beneficiary of that abuse.

Thus, the appointment of Abrahams was unconstitutional as well. The matter came to the Constitutional Court after the North Gauteng High Court in Pretoria declared, in December 2017, that Zuma's conduct in the matter was unconstitutional.

The Constitutional Court also found that certain sections of the NPA Act were constitutionally invalid. Parliament has been given 18 months to amend the NPA Act.

President Cyril Ramaphosa was also ordered to appoint a new NDPP within 90 days.