Former BBC producer Gareth Davies — who has worked with some of the biggest female pop singers in music history — says Shania Twain was “one of the biggest divas” he met during his time in the industry.

“With Shania Twain, as soon as she was asked to come on stage at ‘Top of the Pops,’ there was this very long line of entourage running one after the other, almost like a conga,” Davies recalled in an exclusive interview with Page Six, referring to the popular British television program.

Davies claimed that Twain “doesn’t open doors,” prompting her team to race ahead of her to ensure they reached each exit first.

“They were basically all running to the next door, the next door, the next door through the BBC corridors to make sure that when Shania started walking, she didn’t have to slow down at any point,” he said.

“It was quite fascinating to see … It was sort of like this regimented, rehearsed line that if someone faltered, if someone didn’t get to the door before Shania did, they might be in trouble,” he claimed, describing it as feeling “a little bit overkill.”

The former stage manager then dubbed Jennifer Lopez the “sassiest” celebrity he’d ever encountered.

“I think she’s sort of perhaps built a career on being the queen of sass in a way,” Davies said.

The founder of The Presenter Studio explained that he also worked with J.Lo behind the scenes of the BBC’s popular “Top of the Pops” program.

“She had all her dressing rooms decorated in white,” Davies recalled. “It was like this white plastic film that went everywhere.”

Davies explained that the dressing rooms were “really old-fashioned” and small.

“She managed to take over a whole corridor and got all of those rooms decked out [in] white, which for the BBC back in those days, this felt very unusual,” he said.

Davies also said that the “Love Don’t Cost A Thing” singer required a white microphone on stage.

“A lot of time, money, and effort was spent on making sure that J.Lo perhaps felt as sassy as what she kind of wants to be backstage,” Davies said, adding, “That was fun to see.”

A rep for Twain had no comment when contacted by Page Six, while reps for Lopez did not return Page Six’s request for comment.

As for which celebrity had the biggest entourage, Davies said Madonna arrived on set with a massive posse.

“The only story I can kind of remember, which I suppose is quite a funny story to share, was Madonna had a really big entourage when she arrived,” he said, noting that other singers like Macy Gray show up on their own.

“Everyone’s got their very specific role within quite a big machine,” he explained in regard to Madge’s camp.

Davies recalled a minor blip when Madonna’s stylist “comically” left all of the pop star’s outfits back at her hotel — which was a far drive from the studio.

“She kind of had that one job just to bring the outfits, but didn’t bring them, which I thought was very funny,” he said, adding, “But I didn’t see any fireworks off the back of that, and certainly the fireworks would have been hidden from Madonna.

“You can still have a massive entourage, but sometimes the simple things don’t quite go right,” he said.

Some celebrities may seem like divas onstage, but are anything but that behind the scenes.

“Janet Jackson was one where we were waiting for quite a long time for Janet to arrive and expecting Janet to be really late and just hanging out on the stage with all of Janet’s back-up dancers,” Davies recalled. “Everyone was just assuming that Janet was going to be late until someone pointed out that Janet Jackson had been there the whole time and was just sitting on the studio floor just waiting for us rather than it being the other way around.

“So that was really sweet to see that sometimes you expect someone to be this huge diva and to make an entrance and actually she’s just been waiting there for us the whole time, which I thought was really lovely.”

Unlike Jackson, Simon Cowell isn’t very prompt, according to Davies.

“I’ve not worked with Simon Cowell for a long time, but I know he’s famous for being incredibly late when it comes to the recording of his show,” Davies said, adding, “I think obviously as time has gone on, the world now waits for Simon Cowell rather than the other way around.

“I think sometimes being fashionably late can come with the status,” he added.

Other A-listers whom Davies has found to be surprisingly down-to-earth backstage include Britney Spears, the Spice Girls and Kylie Minogue.

“I think so many of the stories that I have are about [famous] people being really normal, nice and sweet,” Davies said, sharing that, in his experience, celebrities are often “the opposite” of their public personas.