US celebrity Billie Eilish was supported by followers via her Electric Picnic gig after complaining of feeling "really, really sick".

The crowd sang alongside to hits together with Happier Than Ever after the 21-year-old advised her 110 million Instagram followers she was "really suffering" forward of her headline efficiency on the Irish pageant on Friday.

Videos posted on social media confirmed her delivering her Barbie soundtrack tune What Was I Made For? in a white Nike shirt and baseball cap.

Eilish had beforehand requested her followers to assist her on the live performance.

"I am really, really sick, and honestly really suffering," she wrote on her Instagram story.

"You know me and you know that I wouldn't cancel a show even if I was like literally dying… (this does feel pretty close tho lol) but the show must go on.

"I'll see you tonight! But please needless to say I'm attempting my greatest and I'm gonna want your assist tonight. Go onerous for me."

Meanwhile former One Direction star Niall Horan, who sang Sinead O'Connor's hit Nothing Compares 2 U in tribute to the late singer, referenced his native roots in an emotional speech on the pageant.

The Westmeath-born singer advised the gang: "I want I may put into phrases how this felt. From Patrick Street, Mullingar, to this.

"This is a country with less than five million people, and the noise that we make worldwide is insane, and as long as you would like me to, I'm happy to fly the flag for our little country all over the planet.

"I love our little country. I love being here tonight. I love you all. Thank you so much for coming out to see me.

"This is by far the most important viewers I've performed to as a solo artist and I actually recognize it, the assist from my residence nation.

"It's great to be back in the Midlands, only an hour away from home, and have this. Thank you all so much."