Hugh Jackman, Suki Waterhouse and Idris Elba have tackled John Lennon's peace anthem Imagine as part of a global Unicef campaign.

The actors join singers Nicole Scherzinger and Katy Perry on the new cover track, which has been released to mark the 25th anniversary of the Convention on the Rights of the Child - an international agreement by governments to recognise the needs of children.

Members of the public have been invited to record their own version of the song online to create what the charity hopes will become a huge choir hit when the track is released at the end of the year (14).