Ghana's President John Dramani Mahama, the current head of the ECOWAS West African bloc, arrived in Togo on Tuesday on a mediation mission after the opposition complained of irregularities in Saturday's presidential vote.

Mahama was accompanied by Ivory Coast President Alassane Ouattara, who would also take part in the talks between political parties, the Togolese presidency said.

Results from 11 of Togo's 42 voting districts put President Faure Gnassingbe comfortably ahead of his opposition rivals, after he won nearly three-quarters of the valid votes counted.

Togo's main opposition candidate complained on Monday of widespread irregularities and called for the announcement of results to be halted.

Gnassingbe is widely favoured to win a third term, extending his family's long hold on power. He has held the presidency since 2005, when his father died after 38 years in charge.

Some observers voiced concern that mounting political tensions could lead to a repeat of electoral violence seen in 2005, when hundreds were killed.

Opposition leader Jean-Pierre Fabre's CAP 2015 coalition sent a letter on Monday to Issoufou Taffa Tabiou, the head of the election commission, laying out a series of complaints.

The letter said that the initial figures produced by the election commission did not match the results CAP 2015 members had recorded at polling stations.

West African and local election observers said on Sunday the election had taken place without major incidents, although turnout appears to have been low at just over 50%.