In the week since rumors first began percolating that Justin Timberlake and Cameron Diaz may have gone belly-up, he's been linked to no fewer than three different blondes (don't worry, none is Britney Spears).

Not only did the "SexyBack" singer supposedly hang out with Kate Hudson at her New Year's Eve bash and spend time with ex-girlfriend Veronica Finn during a Christmas visit with his family in Tennessee, now there's chatter that he's getting chummy with the Sexiest Woman Alive.

London's tabloid-tastic News of the World claims Timberlake, 25, is "cozying up" to Scarlett Johansson, 22, who recently starred as his love interest in the video for "What Goes Around ... Comes Around," the third single off his chart-topping "FutureSex/LoveSounds" album.

"He's got a tour coming up this year and wanted to concentrate on that, but it seems he's really hit it off with Scarlett while working on the video," a mole alleges to the paper.

The circumstantial courting evidence: Hours after Wednesday's Los Angeles premiere of Justin's long-delayed drama "Alpha Dog," which he attended sans Diaz but with his mom, Lynn Harless, he was spied bending Scarlett's ear at a club.

The baby-faced crooner engaged in an "intimate" hour-long tête-à-tête with the pneumatic actress before his mom got in on the confab, says People.

A little later, as Timberlake hung with his "Alpha" co-stars, Johansson and Harless enjoyed some girl-talk, with the two reportedly gabbing until 2 a.m., when mother and son made their exit through a back door.

So is there a romance a-bubbling between the two stars? When we contacted Scarlett's rep for comment, he downplayed the dating claims and played up the pal angle.

"It is true that Scarlett Johansson worked on a video with Justin Timberlake a couple of weeks ago," the spokesman explains to MSN.com. "Their professional relationship has transpired into a friendship -- nothing more, nothing less."

Justin, for his part, has kept his cakehole closed over what, if anything, has "transpired" in his nearly four-year-old romance with Cameron while making the promotional rounds for "Alpha," although he did tell the Toronto Star, "I can't talk about it right now" (Diaz has also yet to comment on this umpteenth round of rift murmurs).

Meanwhile, Johansson, who was seen spit-shining the tonsils of fitful flame Josh Hartnett in mid-December, just days before he reportedly got up close and personal with the lips of leggy supermodel Gisele Bundchen, is on the defensive over accusations she exhibited some high-maintenance behavior while filming Timberlake's video.

According to E!'s Ted Casablanca, the comely starlet allegedly complained about not being able to puff away on her cancer sticks during the shoot, grumbling, "How come we have fire dancers, but I can't smoke?"

Johansson is also accused of acting up when crewmembers began noshing near where she was standing.

"She had her bodyguard come over and tell them they couldn't eat around her," maintains a mole.

Not true, her mouthpiece insists to the New York Daily News, saying, "Scarlett is always respectful of other people and never made this statement."

What's more, he adds to the paper, "Scarlett doesn't have a bodyguard."