Sao Tome poll to go to second round after first results revised

São Tomé (AFP) - Election officials in the small African state of Sao Tome and Principe have revised weekend presidential poll results that handed a slim winning majority to the ruling party's candidate, opening the way to a second round.

The Independent Democratic Action party had celebrated on Sunday night after the election commission said its candidate, Evaristo Carvalho, had crossed the threshold for an outright victory by winning 50.1 percent of votes cast earlier that day.

But on Friday the commission said it had to "modify these provisional results" -- which gave incumbent President Manuel Pinto da Costa 24.8 percent of the vote -- to take into account tallies of ballots cast by voters in the diaspora and because voting had been delayed in one district.

"No candidate managed to win more than half of valid votes cast," the commission said, adding that this opened the door to a second round of voting.

It is the constitutional court in small islands nation -- located 300 kilometres (190 miles) off the coast of Gabon -- rather than the election commission, that issues definitive results.

No date for a second round has been set.

After the first results gave former prime minister Maria das Neves 16 percent of the vote, his campaign manager said the election "was neither free, nor fair or transparent" and that "results had been manipulated... in favour of the ruling party."

President Pinto da Costa also challenged the initial results.

Executive power in Sao Tome and Principe is shared between the president and the prime minister and has led to turf wars in the past.