Republican Secretary of State Brad Raffensperger on Friday certified the state's election results, which had Biden beating Trump by 12,670 votes out of about five million cast, or 0.25 per cent.

Republican Governor Brian Kemp then certified the state's slate of 16 presidential electors.

Georgia law allows a candidate to request a recount if the margin is less than 0.5 per cent. The recount would be done using scanners that read and tabulate the votes.

County election workers have already done a complete hand recount of all the votes cast in the presidential race. But that stemmed from a mandatory audit requirement and isn't considered an official recount under the law.

Trump has criticised the audit, calling it a "joke" in a tweet that claimed without evidence that "thousands of fraudulent votes have been found".

Twitter as flagged the post as containing disputed information.

Votes that hadn't previously been counted were found in several counties during the audit, which required recertification of the election results in those counties before state certification of the results.

Australian Associated Press