The 70-year-old Rolling Stones rocker was photographed smiling and having fun with a mystery brunette on the balcony of a hotel room in Switzerland last weekend, reported Contactmusic.
"He's a single man and he's Mick and he's having some fun. No one has a clue who this girl is -- not even the security people," a source said.
The singer was left devastated when his partner L'Wren Scott, 49, killed herself in her Manhattan apartment on March 17, but the new pictures with an attractive woman several decades younger than him suggest that he's starting to put the tragedy behind him.
The pair reportedly met at a nightclub in Zurich, where the Rolling Stones were on tour, and spent last Saturday and Sunday enjoying each other's company, before emerging on the balcony on the final day looking dishevelled as the brunette beauty attempted to steal a kiss from the rocker.
The Rolling Stones, also consisting of Keith Richards, 70, Ronnie Wood, 67, and Charlie Watts, 73, cancelled their gigs in Australia and New Zealand in March while Mick grieved for L'Wren, whom he had been dating for 13 years.
The band resumed their '14 On Fire' tour 12 days ago in Oslo, Norway, and are set to perform at the Pinkpop Festival in Holland.