The Australian pop star - who has largely remained single since splitting from former wife Katie Price in May 2009 - is said to be "head over heels" for model Elen Rivas after a string of secret dates in the last few months.
A spokeswoman for the pair told BANG Showbiz: "I can confirm that Elen and Peter are in a relationship - no further comment will be made."
A source close to Peter added: "Pete has fallen head over heels for Elen. For him to admit he is seeing her, it must be serious."
Peter and Elen - who previously dated British soccer star Frank Lampard - were spotted enjoying a romantic dinner at London hotel Claridges before getting into a taxi to see stage production `Flashdance`, and the `Behind Closed Doors` hitmaker has reportedly been gushing about his new love to friends.
He is quoted by the Daily Star newspaper as telling pals: "She is so classy and beautiful, just the change I needed after everything that has happened in the past two years."
Peter`s ex-wife Katie has not directly commented on the 37-year-old star`s new romance, but admitted she believes 35-year-old Elen to be "nice".
She posted on her twitter page: "One of my best friends Andrew Gould said Elen was nice as they ran the marathon together last year x" (Sic)