PETALING JAYA, June 24 — Pop icon Billie Eilish revealed that she used a body double onstage for her performance at Coachella this year and "nobody ever knew”.

In a recent appearance on The Matt Wilkinson Show, the singer admitted that her double - a backup dancer - was briefly playing her onstage during the introductory sequence of the festival.

"We got a black wig, and we put buns in it, and we gave her a mask and sunglasses, and she wore my shoes and my socks,” said Eilish.

"I put her up at the back of the stage and she stood there while the lights went on and everybody thought it was me ― and nobody ever knew it wasn’t me, literally nobody knew.

"And while she’s up there, I put on a big black coat and a traffic vest and a hood and just glasses.” Coachella, or the Coachella Valley Music and Arts Festival, is an annual music festival held at the Coachella Valley in the Colorado Desert, US; this year’s event was held in April.

Eilish was responding to a question on whether she had gone undercover at festivals to watch other artists perform when she was not needed onstage.

After saying that she has done so "occasionally in different places”, Eilish went on to reveal her Coachella secret.

The singer-songwriter will make her debut performance in Kuala Lumpur on August 18 as part of her Happier Than Ever World Tour.