After nearly three rocky years, Justin Timberlake and Jessica Biel have called it quits, Us Weekly reports in its latest issue (on newsstands now).

A mutual pal of the pair tells Us Weekly that Timberlake, 28, has told friends, "it's over," and that he ended it for good — over the phone.

"It was about a month ago," the pal says.

While he was in NYC in September to show his William Rast clothing line at Fashion Week, "Justin was clearly on the hunt," the pal tells Us Weekly.

At a club September 9, he dirty-danced with a tall blonde in a short black dress. At one point, she turned to her friend and mouthed, 'Oh, my God!'

It was reminiscent of Timberlake's guys' night out in June when he was allegedly spotted kissing a girl at NYC hot spot Avenue. Fellow clubgoer Lindsay Lohan Twittered that night, "So dark — where's jb cheater?" She later claimed her account had been "hacked," though another source tells Us she panicked after Timberlake "told all his people" to ban Lindsay and make her life miserable."

Meanwhile, Biel, 27, is in "severe denial and won't accept" the split, their mutual pal tells Us Weekly.

Another source says, "There's no way of knowing if it's a firm breakup, because with them it's so hot and cold."

For more — include how Biel's insecurities drove them apart, how his wandering eye left her "in tears" and why she refuses to let him go — pick up the new Us Weekly today!