The 2006 song has garnered international critical acclaim, winning Winehouse three Grammy awards and an Ivor Novello prize for songwriting.

And Ronson - who produced the track for Winehouse's LP Back to Black - had no idea Rehab would become such a phenomenon.

He says, "Doing Back to Black with Amy, we felt no pressure at all to come up with hits. We were in our own bubble, just making music we liked.

"So while I knew it was good, I had no idea why her A+R guy saw dollar signs the very instant we first played him Rehab."

Source: WENN