The Independent Electoral Commission's regulations barring South Africans working abroad from voting are unconstitutional, the Democratic Alliance said on Monday.

Briefing the media in Cape Town, DA Federal chairman James Selfe said the party last week filed papers in the Cape High Court to have section 33 (1) (e) of the Electoral Act that bars SA expatriates from voting, declared unconstitutional.

"The denial of the right to vote to the vast majority of 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," Selfe said.

The Electoral Act only allowed citizens who are abroad on holiday, business, study and international sports, to cast their ballots from outside the country.

"Except for South Africans serving in diplomatic missions, these are only permissible grounds for applying for a special vote if one is outside the country," Selfe said.

The restrictions gave rise to all sorts of anomalies and unintended consequences, "which are clearly unconstitutional".

"It discriminates unreasonably between various classes of South Africans temporarily outside the country," Selfe said.

Meanwhile, the Freedom Front Plus said it would submit an application to the Constitutional Court in a bid to have the same regulation declared unconstitutional.