She’s well known for her wild behaviour, smoking weed and drinking before her stage shows.

But diva Miley Cyrus left her Melbourne audience stunned when she took her wild antics a step too far, flashing her private parts, legs akimbo, staging a mock orgy and straddling a giant hotdog at her Bangerz concert.

The 21-year-old Wrecking Ball singer left shocked parents covering their children’s ears and eyes as she stomped on stage unleashing a string of expletives on Friday night.

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Kicking off her first show Down Under, the former child star burst onto the stage at the Rod Laver Arena perched on a giant tongue and declared: ‘Melbourne, I want to hear some mother f*****g noise.’

Stomping on a gold car, she then stroked herself, legs akimbo, telling fans:’ This is the first time we’ve done the whole f*****g show. 

‘South America couldn’t handle the giant tongue and the sex. I got so drunk at other shows, puking at the side of the stage.’

She went on: ‘And you cant be under the influence at shows when you’re gyrating on f*****g cars, so I’m sober, well, sober-ish.

‘I’m trying to create some memories for you mother f***ers here. I’m talking to f*****g much. My next song is called Darling.’

The sexually explicit show, which saw her don a prosthetic bottom, left some parents agog, while others stormed out.

Rea Philips, 23, who took her niece Mia, eight to the concert, told Daily Mail Australia: ‘It was so inappropriate I had to cover Mia’s ears and yes. 

‘She [Miley] was saying the F-word too much, it was pointless. I feel really bad I brought Mia along.’

Another mother of two boys aged 12 and: ‘We knew it would be like this but she’s outrageous.We left early, I don’t my sons hearing that stuff. it’s disgusting.’

Even fan Elly Shaananpour, 13, from Doncaster in Melbourne, said she was left speechless by Cyrus’s stage antics.

‘My mum still thinks she’s like Hannah Montana so she has no idea what she’s like now. She won’t be happy.’

Miley, known for her love of twerking and tongue wagging, says she never likes to disappoint on stage. 

Gyrating and rubbing up against her backing dancers, she showed just exactly why her world tour is called the Bangerz.

At one point she staged a mock orgy on a giant bed before going on to gyrate astride a giant hotdog.

Then, she took a swig from a water bottle before spitting out the contents of her mouth onto baying fans telling them: ‘For f*****g Australians, you all seem very afraid of water.’

The ex-girlfriend of Australian heartthrob Liam Hemsworth rocked a series of glittering ensembles including a sunset orange yellow skintight top and high-waisted pants that showed off her taut stomach.

She added glitter to her eyes and a swathe of yellow fur to complete the look.

The night before, the pop singer went to Collingwood tattoo shop Eureka Rebellion with her brother Braison to get some fresh ink.

She got a small design on her wrist while her sibling Braison got a medium-sized one on his forearm. 

Next Miley will head to Brisbane, followed by Sydney for two shows before taking the stage in Adelaide and Perth.