The applicant in the case to get political parties to disclose their sources of private funding says the Western Cape High Court's ruling upholds voters' right to be informed.

Non-profit organisation My Vote Counts (MVC) welcomed Wednesday's ruling that the Promotion of Access to Information Act (PAIA) be amended so political parties can disclose their sources of private funding.

The right to vote was "the right to make an informed vote", MVC national coordinator Janine Ogle said on Wednesday.

"We have always argued that PAIA does not allow for access to information about political party funding, this judgment proves this," Ogle said in a statement.

"We welcome the Court's pronouncement that political party funding information is required in order to make an informed political choice; this means that there must be a legislative mechanism that allows access to this information."

Judge Yasmin Meer ruled that information about private funding is "reasonably required" for the effective exercise of the right to vote and to make political choices by the Constitution.

The request for mere disclosure therefore could be granted, through an amendment of the PAIA, she said.

Meer though said the courts could not dictate the manner in which Parliament orders parties to disclose that information, leaving that process up to Parliament to determine.

Parliament has 18 months to rectify "inconsistencies" in PAIA.

Ogle acknowledged that Parliament has already started its own ad hoc committee process to review the rules on disclosure of party funding.

A draft bill was gazetted last week, with a view to finalising a bill in November.

DA opposes the application

"The current process in Parliament to repeal and replace the Represented Political Parties Act may produce that legislation and therefore we are following that process closely."

The new legislation must enable an open and transparent political party funding system, she said.

Democratic Alliance (DA) federal council chairperson James Selfe told News24 on Wednesday that they will consider the judgment carefully.

The DA was the only political party to oppose the application.

Selfe said the party acknowledged that disclosure was important in relevant cases to avoid "pernicious" influence of big donors and state capture, but that smaller donors could feel victimised if forced to disclose their donations.

The question now is whether PAIA should still be amended if Parliament passes standalone legislation as a result of the ad hoc committee process, which lays out in detail the extent of disclosure, he said.

The United Democratic Movement (UDM) meanwhile welcomed the decision, saying it was a victory for democracy and accountability.

The party believed the review of party funding legislation was necessary to eliminate the trend of "selling the country to the highest bidder", as shown by the #GuptaLeaks, it said.

Public funding of political parties too should be regulated by law, with an equitable distribution formula, the UDM added.

"The electorate needs to know, and hold political parties accountable on how they run their affairs."