Victoria Beckham realised her Spice Girls career was finished in 2008.

There have been rumours the star and her bandmates Mel B, Geri Halliwell, Mel C and Emma Bunton were considering reuniting to mark their 20th anniversary next year. Speculation claimed Victoria was the main sticking point and she has now confirmed she won't be picking up the microphone again.

Although the five-piece performed at the London 2012 Olympic Games, the 39-year-old star knew she'd grown apart from her bandmates years ago.

"I realised it was finished for good in 2008, when we reformed for our reunion tour. The day of the concert at Madison Square Gardens in New York, the other girls spent time relaxing in bed, shopping and in the gym before heading off to the sound check," she recalled to Paris Vogue. "I arrived with three kids in tow in a really tight dress because I’d been in meetings all day.

"I put my bags and the children down, I picked up the mic and I sung. It should have been the best moment of my life, but I just wanted to be elsewhere."

Victoria quickly pointed out it wasn't a lack of respect for the Spice Girls which made her feel that way. Instead she realised she didn't feel passionate about being on stage, in marked contrast to the excitement she experiences when working on her fashion lines.

The star never really felt comfortable when on stage or promoting her music, which she claims is why she often came across as grumpy.

"I looked moody. But I wasn’t! I was shy, not very sure of myself," she insisted.

"The other girls would sing and dance on tables with no complexes, I wasn’t confident enough to do that. I had to invent a character and I thought of that: staring at people and pouting.

"My insecurities helped me create the character in a way. Nowadays, it’s like a barrier that comes back whenever I go out in public. That’s the way fame has affected me."

Hinting things got a lot worse than many know, Victoria opened up about her family's move to Los Angeles when her husband David signed with a soccer team out there.

"It could have been a lot worse: I don’t have a single stint in rehab to my name," she mused.

"I feel more free these days. Someone said to me once, LA’s like a giant rehab centre for celebs. Everyone walks around in casual clothes. It’s so far away from everything that people leave you alone."

The couple share four children, the youngest of who is two-year-old daughter Harper. Victoria is determined to be there for the little ones and claims she does everyday things with them, such as shop for food in supermarkets.

"I go down the aisles telling the kids, 'No, you can’t have that!', just like any other mother. People look at me in awe like I’m from the circus, but it doesn’t bother me," she laughed.