Peterborough United sign young prospect on a two-year pro deal
and live on Freeview channel 276
Mills was reportedly being monitored by Premier League side Crystal Palace earlier this year. He moved to Posh from Aston Villa in 2021.
Posh Academy coach Jamal Campbell-Ryce said: “Harley has been outstanding since the turn of the year and has fully deserved this opportunity.
"Harley has shown how much he values defending and has real quality when in possession of the ball. He has a wonder of a left foot. We are delighted that he has agreed a contract with the club."