Lets get limber! Margot Robbie and Phoebe Tonkin go head-to-head as they try and outstretch each other on social media

They may be competitive, but Margot Robbie and Phoebe Tonkin's friendship is being stretched to the limit.
The Australian actresses have leapt into to xtend barre craze and are battling it out on Instgram to prove who is the ultimate black swan.
Combining elements of pilates and dance, the work out is a form of total-body training and sculpting exercises that use a ballet barre.

Firing the first shot, Tonkin, 24, posted a photo on her Instagram about two weeks ago with a leg stretched in the air as she worked out on a piece of equipment.

A week later, on her newly created Instagram account, 23-year old Robbie returned fire by sharing an image of herself hanging from bars with one foot on a mat and a leg outstretched.
'I can do it too @phoebejtonkin,' she posted.

Not wanting to be outdone Tonkin shared an image of Wednesday working out in a black tutu reminiscent of the 2010 Black swan movie.
'And you thought you could out black 

swan me @margotrobbie well it's #tututuesday at @balletbodies yo x,' she posted.The Wolf of Wall Street is yet to respond to the latest installment in this healthy competition.
In March, Robbie finally bowed to peer pressure from friends and fans and joined Instagram and the two weeks since she joined, has amassed more than 47,000 followers. See more