Katy Perry cheekily flashed her sparkly sequin bra as she slipped into a very skimpy outfit for a show in LA on Saturday night.

The singer, 40, was performing at the El Rey Theatre where she was a special guest of songstress Rebecca Black.

And while on stage Katy clearly got very into her performance as she lifted her тιԍнт white vest down to reveal her silver underwear.

She completed her outfit with a tiny black and silver mini skirt with buckle detailing and boosted her height with silver heels. 

At the show Katy announced that she will be supported by Rebecca, 27, on The Lifetimes Tour which begins next month.

The Firework hitmaker was a surprise guest at the Friday singer’s concert, with the pair joining forces on a rendition of Perry’s 2011 hit Last Friday Night (T.G.I.F.) – 14 years after Black made a cameo in the music video.

Katy Perry cheekily flashed her sparkly sequin bra as she slipped into a very skimpy outfit for a show in LA on Saturday night

The singer, 40, was performing at the El Rey Theatre where she was a special guest of songstress Rebecca Black

Katy proposed to Rebecca, getting down on one knee to ask if she would open for her on the jaunt.

She asked her: ‘Will you…’

Asking for clarification, Black said: ‘Marry you?’

To which, Perry replied: ‘Kinda, join me on the Lifetimes Tour?’

The excited singer agreed: ‘Yes, yes, yes.’

Perry later posted to Instagram: ‘About to spend a lot more Fridays with @msrebeccablack.

‘WELCOME TO THE LIFETIMES TOUR BABES.’

The carousel included a clip of Perry sharing the tale of how Black came to appear in the Last Friday Night promo.

She recalled: ‘Rebecca and I both love Fridays.

‘So that’s why I asked her to be in this music video because Friday is like my favourite day of the week, and it’s her favourite day of the week.’

And while on stage Katy clearly got very into her performance as she lifted her тιԍнт white vest down to reveal her silver underwear

She completed her outfit with a tiny black and silver mini skirt with buckle detailing and boosted her height with silver heels

At the show Katy announced that she will be supported by Rebecca, 27, on The Lifetimes Tour which begins next month

She put on a confident display as she showed off her figure in the skimpy sequin bra while taking to the stage 

The Firework hitmaker was a surprise guest at the Friday singer’s concert, with the pair joining forces on a rendition of Perry’s 2011 hit Last Friday Night

Rebecca seen performing last year 

She went on: ‘We used to be friends in 3rd grade and then something happened. I don’t know what happened, but…’

Black added: ‘This happened.’

Perry then quipped: ‘Well, I’m sorry I’m not a C cup.’

The Lifetimes Tour kicks off on April 23, in Mexico City, and is set to conclude on November 11, in Madrid, Spain.

Perry’s last concert trek was 2017 and 2018’s Witness: The Tour.

Teasing what fans can expect, Perry told Rolling Stone: ‘We’re giving BPM. We’re giving celebration. We’re giving unity. We’re giving dance.

‘It will be like Disneyland on Wheels, as it always is. A feast for the eyes and the ears.’