The Freedom Front Plus and Democratic Alliance have filed court challenges against electoral regulations barring South Africans working abroad from voting.

The FF Plus filed papers in the Pretoria High Court on Monday challenging the constitutionality of this provision in the Electoral Act.

"This is only the first step and we will approach the Constitutional Court if it becomes necessary," warned FF Plus leader Pieter Mulder.

He has charged that there were political and not constitutional reasons behind the changes to the Act, which in 1994 allowed all South Africans abroad to vote.

As it stands, the Electoral Act allows applications for special votes only by South Africans temporarily absent from the country on holiday, business trips, at tertiary institutions, on educational visits, participating in an international sporting events, or stationed at diplomatic missions.

"By treating me on an unequal footing compared to other citizens is infringing on my dignity and personhood," argued Willem Richter, 27, a South African teacher working at a school in Surrey in the United Kingdom.

His urgent application, brought with the FF Plus, against the Ministers of Home and Foreign Affairs and the Electoral Commission will probably be heard in the Pretoria High Court on February 3.

"We feel you cannot stop a South African from voting. One of your rights as citizen is to vote," said Mulder.

The DA filed papers in the Cape High Court last week, also seeking to have the section declared unconstitutional.

DA federal chairman James Selfe argued on Monday that the denial of voting rights to most South Africans was central to the struggle against apartheid.

"Because of the importance of the right to vote, this right is guaranteed to all adult citizens in the Bill of the Rights," he said.

The restrictions in the Act gave rise to all sorts of anomalies and unintended consequences, "which are clearly unconstitutional" including unreasonable discrimination between various classes of South Africans temporarily outside the country, he said.

In a letter to Independent Electoral Commission (IEC) chairwoman Brigalia Bam, last week, former president F W De Klerk urged her to urgently reconsider the matter urgently "since immediate steps will have to be taken to register" South Africans living abroad in time for the election.