DPP Noordin Haji has ordered the release of blogger Cyprian Nyakundi from Muthaiga police station.
Nyakundi was first arrested on April 28 following allegations that he abused Nairobi Governor Mike Sonko on social media.
He was freed and re-arrested on May 14.
Haji directed the investigators to present his file in court with the aim of withdrawing and marking the case as closed.
"No criminal charges should be registered against the above named individual pursuant to the miscellaneous application without my express approval, " Haji said in a letter.
He added that his offence of misdemeanour and abuse of cyberspace does not necessitate a detention period of three days
The letter dated May 16 was addressed to the senior director of public prosecution and copied to the director of criminal investigations and Nyakundi's lawyer.
Tweeting from the police cell, Nyakundi said the Directorate of Criminal Investigations brought four cases against him.
He said Sonko, Kirinyaga governor Anne Waiguru, NCIC, and Kenya Power MD Ken Tarus are the complainants.