Superproducer Mark Ronson has branded British singer Lily Allen "rude" - after she ignored his attempts to get in touch. The star collaborated with Ronson on debut album Alright, Still, and sang on Ronson's reworking of the Kaiser Chief's Oh My God, but has failed to answer his phonecalls. And Ronson is surprised the Smile star isn't keen to work with him again. He says, "Lily has been working on her new album but I'm probably not going to be on it as she hasn't been returning any of my calls. Most of the people I work with, I'm lucky enough to be friends with too. But then you never really know what's going to happen after that." But the producer insists a failed appearance from Allen at the BBC's Electric Proms in October (07) did not signal the beginning of the feud. He explains, "She didn't come but she had another commitment and she explained why and that's fine. I'm not going to lie and say I wasn't disappointed - but it's not like she just didn't show."