When walking the streets of London she looks made up to the nines. But when it comes to rehearsing a number, Lady Gaga likes to take it all off.

On Friday, the Applause singer hit a London stage wearing just a bra and pantyhose to practice the songs that she will sing for a packed audience.

The 27-year-old entertainer is the opening act for the month long iTunes Festival, which begins on Sunday.

Singing her heart out: Lady Gaga belts out a song during her rehearsal for her iTunes Festival appearance in London

Fans were given a sneak peak of Gaga’s latest song Manicure, which she will debut at the fest, via a rehearsal video posted to the star’s Youtube page.

Almost unrecognisable in a skimpy black bra and very tight yet semi-sheer capri pantyhose with stringy dark hair piled up into a lazy bun, Gaga looked totally out of her element.

In uncharacteristic fashion the star gave a rousing but stripped down performance without the aid of props or wild over-the-top costumes.

Dress rehearsal: Two backup dancers fitted Gaga into some sparkly boots while she rehearsed her new rock anthem Manicure

Sultry performance: The Applause singer showed off her dance moves

The Grammy winner didn’t hold back either. She gyrated like crazy, hunching down, twisting and turning to get into the performance.

At the beginning of her rehearsal number for her rock and roll anthem Manicure the singer was dressed in only sheer stockings and a bra.

But she was soon strapped into a pair of sparkly boots by two of her assistants, while she belted out the song onstage.

Lady Gaga strips down to her bra and tights for rehearsal videoLoaded: 0%Progress: 0%0:00PreviousPlaySkipMuteCurrent Time0:00/Duration Time1:03FullscreenNeed Text

The big gesture: The 27-year-old shook her hands in unison with her crew

Breaking it down: The pop sensation stomped her feet on the ground as she reached deep for a vocal blast

As Gaga was strapped into the 𝑠e𝑥y boots she seemed to be barely paying attention as her minders dressed her.

The Applause singer, born as Stefani Joanne Angelina Germanotta, then engaged in a choreographed dance routine with her backup crew, who writhed and contorted around her in a sultry and sweaty rendition.

At one point her backup performers raised their arms over their heads and sensually swayed in a wave motion as the pop star unleashed her vocal power with startling force – proving that festival goers are in for a rare treat.

Laying down the number: The singer, whose birth name is Stefani Joanne Angelina Germanotta, showed some attitude

Modern pop: The dancers showed off their jazz hands near the end of the rendition

Gaga has been making several appearances since she arrived in London and is expected to stay for several more days.

Her album ARTPOP, her third studio produced effort, doesn’t drop until November 11.

Meanwhile, Gaga already has plenty to celebrate as her new single Applause – off of her upcoming album – reached number four in the Billboard Hot 100 chart this week.

A bit more covered up: The Poker Face singer often hits the streets in wild costumes as seen on Thursday in London

She is also promoting her new album in the US and the UK and is expected to debut lots of new material during her concert performance this weekend.

On Wednesday she released a minute long snippet of her new song Swine. The lyrics include, ‘I know, I know, I know, I know you want me / You’re just a pig inside a human body / Squeal, squeal, squeal… / You’re just a pig inside, swine.’

She later added a few more Swine lyrics onto her Twitter account: ‘Maybe I should have a little more / Just to stay out of my mind? / ‘Cause it’s when I’m not thinkin’ with you / That I act like a swine.’