Kenya's opposition leader Raila Odinga has withdrawn his candidacy for the fresh presidential election ordered by the country's Supreme Court, saying the election commission has not made the changes to avoid the "irregularities and illegalities" cited in the nullified August vote.

Odinga made the surprise announcement Tuesday. It was his legal challenge that led the court to nullify the 8 August election that President Uhuru Kenyatta won.

The court also ordered a new election, which is set for 26 October. It was the first time a court had overturned the results of a presidential election in Africa.

Odinga says "there's no intention" on the part of Kenya's election commission to undertake any changes before the vote.

He said the commission had "stonewalled" reforms the opposition had sought and wasted time in "public relations exercises" meant to create an impression of "motion without movement."

Among the reforms Odinga had demanded were the replacement of suppliers of equipment used to transmit election results and the replacement of electoral officials the opposition claimed were complicit in electoral fraud.