The Supreme Court annulled last month's vote, citing irregularities. It was won by the incumbent Uhuru Kenyatta.

French firm OT-Morpho says it needs to reinstall the complex voting system for the scheduled re-run on 17 October.

But it said the "significant amount of work" cannot be finished in time.

Details of the potential delay for October's re-run emerged in a letter from OT-Morpho to the electoral commission, obtained by Reuters news agency. An election official also confirmed the potential delay to the BBC.

The letter, dated 18 September, said two different electronic systems used in the vote would have to be reinstalled for a re-run.

More than 45,000 computer tablets were provided to Kenyan officials to identify voters - using fingerprints and photos - before allowing them to vote.

The tablets were also responsible for the secure transmission of election results, the company said in an April press release.

Irregularities in the transmission of results was one of the problems referenced by the Supreme Court when it annulled the August poll's results. But more precise details have yet to be released ahead of the court's full report, due on Thursday.

In addition to the technology problems, opposition candidate Raila Odinga - set to contest the election against Mr Kenyatta - has said he will not take part in the re-run unless members of the country's electoral commission are replaced.

The commission has reportedly arranged a meeting with both candidates on Wednesday to discuss potential problems ahead of the poll.