Image copyright Getty Images Image caption The show marked the opening of Eilish's first world tour

Pop star Billie Eilish delivered a powerful message about body shaming as she kicked off her world tour in Miami on Monday night.

The 18-year-old has previously said she wears baggy clothes to avoid being sexualised, and addressed criticism of that choice during a video interlude.

"If what I wear is comfortable, I am not a woman," she said. "If I shed the layers, I am a slut".

"Though you've never seen my body, you still judge me for it. Why?" she asked.

The two-minute video was played towards the end of Eilish's 22-song set, immediately before the song All The Good Girls Go To Hell.

In the visual, Eilish was seen removing several layers of clothing until she was only wearing a bra, before sinking symbolically under the surface of a black, tar-like liquid.

At the end of the clip, she warned against making "assumptions about people based on their size".

"We decide who they are. We decide what they're worth," she said. "If I wear more, if I wear less, who decides what that makes me?

"Is my value based only on your perception? Or is your opinion of me not my responsibility?"

The interlude was just one element of a spectacular live show which began Poltergeist-style, with Eilish dangling on wires underneath a floating bed.

Image copyright Getty Images Image caption The tour is scheduled to play in Manchester, Birmingham and London in July

After falling through the stage, she emerged on a riser at the end of a catwalk to perform Bury A Friend, before running through tracks including You Should See Me In A Crown, Ocean Eyes and her Bond theme No Time To Die.

She played Copycat from a floating walkway above the stage, and showcased her piano skills during a brief instrumental at the keyboard.

During the concert, the five time Grammy-winner dressed in her traditional baggy clothes - with a green sequinned shirt that matched her shorts and black Nike high-top trainers.

For the uptempo songs, she bounded up and down the catwalk, her vocals frequently drowned out by the crowd.

Coronavirus permitting, the tour comes to Europe in July after a 38-date trek across North and South America; with dates scheduled in Manchester, Birmingham and Manchester.

The full text of Eilish's body shaming speech is below:

Do you really know me?

You have opinions about my opinions, about my music, about my clothes, about my body.

Some people hate what I wear, some people praise it. Some people use it to shame others, some people use it to shame me.

But I feel you watching... always. And nothing I do goes unseen.

So while I feel your stares, your disapproval or your sighs of relief, if I lived by them, I'd never be able to move.

Would you like me to be smaller? Weaker? Softer? Taller?

Would you like me to be quiet?

Do my shoulders provoke you? Does my chest? Am I my stomach? My hips?

The body I was born with, is it not what you wanted?

If what I wear is comfortable, I am not a woman. If I shed the layers, I am a slut.

Though you've never seen my body, you still judge it and judge me for it. Why?

You make assumptions about people based on their size. We decide who they are. We decide what they're worth.

If I wear more, if I wear less, who decides what that makes me? What that means?

Is my value based only on your perception?

Or is your opinion of me not my responsibility?

Meanwhile, the IFPI, which represents the music industry worldwide, has named Eilish's Bad Guy as the biggest global single of 2019.

The song topped the charts in 15 countries when it was released just under a year ago.

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