Mulenga who is the son of late President Michael Sata immediately declared that he would apply to contest the vacant mayoral position in Lusaka.
He was welcomed by party Secretary General Davies Mwila at a press briefing today.
Mulenga resigned in the aftermath of a fractious succession wrangle of late President Sata that ushered in President Edgar Lungu.
He later crossed over to the UPND where he contested the Kabwata Constituency seat and comprehensively lost.
The former Lusaka mayor joins other PF bigwigs that had ditched the party and returned.
He described himself as a prodigal son who was returning home.
“I wish to publicly declare that I have resigned from the UPND to re-join the mighty PF. I am the prodigal son who has come back home. I was lost, now I am found,” Mulenga said.
The PF has been reaching out to former members that had left in the aftermath of President’s Sata’s death with former First Lady Christine Kaseba Sata appointed as ambassador to France.