The Western Cape High Court has declared Parliament arsonist accused Zandile Mafe unfit to stand trial.

This followed an inquiry into his fitness to stand trial for allegedly torching the National Assembly building.

On Monday, Judge Nathan Erasmus ruled he was of the view Mafe was incapable of understanding proceedings.

"Therefore, my finding is in concurrence with the experts as it's commonly known that he is not fit to stand trial."

Mafe insisted there was nothing wrong with him, and claimed to have set the National Assembly building alight because Parliament was "useless". 

His counsel, Dali Mpofu SC, said Mafe would appeal the ruling.