Can a photograph define a crisis?

The picture of three-year-old Aylan Kurdi lying face-down on a Turkish beach has provoked furious debate about what the UK and EU are doing to stem the worst refugee crisis since World War II.

Can a photograph define a moment in a crisis and do images still have the impact to change people’s minds?

Nick Ut's picture of nine-year-old Phan Thi Kim Phuc - a young girl, running naked and terrified down the road after a napalm attack - became one of the iconic images of the Vietnam War.

"This child could be any of ours - he's wearing fashionable clothes and is wearing trainers - and has obviously died on his own," said Brett Rogers, director of London’s Photographer’s Gallery.

“But I don’t think it can change issues unless the government wakes up to things today.”

Jenny Matthews a conflict photographer and author of Woman and War, said the picture of Aylan Kurdi was especially poignant as it contrasted with beach pictures of British tourists returning from beach holidays.