Pink Floyd have written their first new song in almost 30 years to support Ukrainians, the band announced on Thursday. 

"Hey, Hey, Rise-Up!" will be released  on Friday, and be used to raise funds for humanitarian causes linked to the war. 

It samples Andriy Khlyvnyuk, from one of Ukraine's biggest bands BoomBox, singing in Sofiyskaya Square in Kyiv in a clip that went viral. 

Khlyvnyukh abandoned a world tour to return to Ukraine and help defend his country. 

"We, like so many, have been feeling the fury and the frustration of this vile act of an independent, peaceful democratic country being invaded and having its people murdered by one of the world's major powers," Pink Floyd said on their official Twitter feed.

In a press release, band leader David Gilmour said he had been moved by Khlyvnyuk's video: "It was a powerful moment that made me want to put it to music." 

He was able to speak with Khlyvnyuk from his hospital bed in Kyiv, where the singer was recovering after being hit by shrapnel in a mortar attack, the record company said.

"I played him a little bit of the song down the phone line and he gave me his blessing. We both hope to do something together in person in the future," Gilmour said. 

The image accompanying the song is of a sunflower, and was inspired by a viral video showing a Ukrainian woman insulting two armed Russian soldiers. 

In it, she tells the soldiers: "Take these seeds and put them in your pockets. That way sunflowers will grow when you all rest here." 

It is the first original music from Pink Floyd since 1994's "The Division Bell". 

Gilmour tweeted his opposition to the war soon after Russia's invasion, saying: "Putin must go". 

The band has also pulled their music from Russian and Belarusian streaming sites in protest at the invasion.