Coldplay invited Ariana Grande on stage at Global Citizen Festival yesterday – watch

Grande and Chris Martin played 'Just a Little Bit of Your Heart' together

During the annual Global Citizen Festival in New York yesterday Ariana Grande joined Coldplay on stage for a duet on ‘Just a Little Bit of Your Heart’.

The ballad, which was penned in part by One Direction‘s Harry Styles, is normally accompanied by piano, but due to Coldplay’s piano breaking was played on acoustic guitar by Chris Martin as he harmonised with Grande.

Coldplay tweeted: “Our piano broke 1 min before going onstage. No clocks, paradise+collaboration with @ArianaGrande rehearsed only on piano #wingingit.”

The order of the day at this free festival was collaborations: Ed Sheeran brought out Chris Martin for ”Thinking Out Loud’, Beyoncé brought out Sheeran for ‘Drunk in Love’ and Pearl Jam brought out Beyoncé for a cover of ‘Redemption Song’.

Watch a clip of Chris Martin and Ariana Grande’s collaboration below:

Coldplay, who are set to release new album ‘A Head Full of Dreams’ some time before Christmas, were also filmed by a fan performing a new song during Global Citizen Fest soundcheck yesterday.

Talking about the new album, Chris Martin said: “It’s our seventh thing, and the way we look at it, it’s like the last Harry Potter book or something like that. Not to say that there might not be another thing one day, but this is the completion of something… I have to think of it as the final thing we’re doing. Otherwise we wouldn’t put everything into it.”

Every Coldplay album to date has been a UK number one, with latest ‘Ghost Stories’ by a distance their lowest seller to date, but still surpassing 600,000 copies sold.