Rehab singer Amy Winehouse has allegedly infuriated incarcerated husband Blake Fielder Civil - by spending a night in a hotel room with music producer Mark Ronson. The talented wild singer reportedly headed back to a London hotel room with Ronson the producer of her hit album Back To Black - at 5.30am on Saturday, after an alcohol-fuelled session in a recording studio on Friday night. The room, at the K West Hotel in Notting Hill, west London, was booked in Ronson’s name - and Winehouse did not emerge until late on Saturday. And Fielder-Civil, who is currently being held on remand at London’s Pentonville Prison on charges of perverting the course of justice, is allegedly devastated by Winehouse’s behaviour. A source tells British newspaper the News Of The World, "It’s the last thing Blake needs to hear right now. He’s furious about how close they are. "Blake’s fearful that Mark has much more in common with Amy than he does and is worried he’ll steal her away." It is yet another blow to Fielder-Civil, who was said to be shocked last week to find his wife had celebrated the New Year's Eve on the Caribbean island of Mustique with ex-boyfriend George Roberts.