It is the curvaceous derrière which launched a modern-day diva.

But as Jennifer Lopez cavorted on stage in an utterly unforgiving diamanté-studded catsuit last night, her once ample bottom appeared to have been downsized.

Suffice it to say, there was no space for any lumps or bumps in a figure-hugging outfit which stole the show.

Scroll down to watch a video

Shrinking star: Once famous for her ample curves, Jennifer Lopez looked slimmer on stage in New York as she celebrated the New Year last night

She teamed the catsuit – which looked see-through under the stage lights – with a pair of matching diamanté studded ankle boots.

The 40-year-old singer was performing her 1999 hits Waiting For Tonight and Let’s Get Loud and her new single Louboutins at Times Square in New York to celebrate the start of 2010.

Despite miserable weather, more than 750,000 revellers braved the cold and rain to watch J.Lo sing. Millions also watched the show on television.

‘You didn’t think I could do that in the rain did you?’ she said after risking a major wardrobe malfunction with a hugely energetic routine.

Showstopper: J.Lo’s skintight diamante-studded catsuit looked semi-transparent under stage lights

Uninhibited: The singer writhed and high-kicked her way through a show watched by 750,000 people

Her audience cheered as she writhed on the stage before high-kicking along to Frank Sinatra’s classic New York, New York.

J.Lo grew up in the Bronx but admitted she had never been to Times Square to celebrate New Year’s Eve.

After her performance, she told host Ryan Seacrest: ‘This is my first time ever coming down here. It’s just so much good, hopeful, amazing, loving energy. I feel like a little girl!’

Seacrest, who was presenting Dick Clark’s New Year’s Rockin’ Eve, couldn’t hide his admiration for J.Lo’s costume.

He grinned: ‘That outfit has made my year!’

Unforgiving: Despite being covered in fabric from head to toe, J.Lo’s outfit was very revealing

End of the decade: J.Lo admitted it was the first time she had been at Times Square for New Year despite growing up in The Bronx