Johannesburg - AfriForum on Tuesday said it was dismayed by the number of international voting stations available for South Africans living overseas.
"It is disappointing that there are so few voting stations abroad, especially in large countries like Australia, the US and Canada," deputy head of AfriForum Alana Bailey said in a statement.
She said the organisation believed that distances, time and costs would deter "many" people from voting.
"We, however, also have sympathy with the fact that every additional voting station brings about a huge financial burden."
The organisation said it would therefore look ahead to the 2018 elections and continue discussions with the Electoral Commission of SA (IEC) to try and find alternatives, such as electronic votes, which could be implemented for expatriates in the future.
On Tuesday, the international relations department said it was satisfied that all necessary arrangements were in place.
Expatriates could vote provided they had applied for a special vote.
"The department is satisfied that it has made the necessary information and infrastructure available for the IEC to carry out its constitutional mandate of managing the electoral process," departmental spokesperson Clayson Monyela said.
The IEC said that more than 26 400 people had successfully applied to cast their ballots abroad.
Expatriates in Auckland, New Zealand, were the first to start voting - from 21:00 South African time on Tuesday.
London had the highest number of expatriate voters at 9 863, followed by Dubai with 1 539 registered voters.
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