The Constitutional Court has confirmed a ruling by the Western Cape High Court which found that the Promotion of Access to Information Act (PAIA) was unconstitutional because it did not provide for the disclosure of information pertaining to the private funding that political parties receive.

Chief Justice Mogoeng Mogoeng handed down his ruling on Thursday morning.

Non-profit organisation My Vote Counts had previously argued in the Constitutional Court that it was critical for voters to know who funded political parties, so that citizens could be informed and make the right decisions.

High Court Judge Yasmin Shenaz Meer ruled last year that Parliament had 18 months to rectify the "inconsistencies" in the PAIA.

Meer said information about private funding was "reasonably required" for the effective exercise of the right to vote and to make political choices.

Advocate Max du Plessis, for My Vote Counts, had previously argued in court that all donations to political parties should be disclosed until Parliament determines the limits.

He told the court that it was critical for voters to know about all the donations to parties and added that this included the use of stadiums and vehicles as an example.

Du Plessis argued there were major problems with the "architecture" of the PAIA and asked the Constitutional Court to suspend the order to allow Parliament to deal with the inconsistencies and problems.