Will.i.am has revealed that it took a lot of travelling to finish shooting his latest music video.

The maestro recently teamed up with Justin Bieber for the track '#thatpower', with the Canadian appearing in its video in hologram form.

Speaking to ET Online, the Voice UK coach said that the 'Believe' star's touring schedule and varying locations made it difficult to shoot the clip. He said:

"[Justin's] on tour. It was tough to get this video [done]. I had to fly to Barcelona to shoot Justin Bieber then flew to Japan to work with Rio and the boys on the choreography for it. So it was a lot of trekking."

Speaking about how the collaboration came about, will.i.am said:

"He was my next-door neighbour last year. And I called him on the phone when I saw his car outside. And he came to the crib and we made that song and then he moved."