British pop star Robbie Williams has suffered a major slump in income over the last few years due to declining record sales, according to his manager.

The Take That's star's longtime aide, Tim Clark of ie:music, made the revelation while addressing politicians at a parliamentary conference debating the future of the record industry.

Clark spoke about his most famous client, revealing Williams is now pulling in only a fraction of the earnings he used to, saying, "I represent Robbie Williams but also a number of smaller acts. But I have got to tell you it is damned difficult. It is difficult enough for Robbie Williams whose revenues from recorded music have plummeted. His revenues are nothing like what they were five or six years ago."

He went on to talk about the impact of the digital music revolution, claiming artists like Williams now have to sell out huge tours in order to make any real money as recorded music revenues are "going down incredibly quickly".

Clark also complained about the amount of extra work which has come with the rise of social media, adding, "The amount of content that artists have to make now is crazy. They are tweeting, they are making stuff for Facebook, they are making stuff for YouTube... It is unbelievable how much stuff artists have to do in order to try and get people (to) come and buy their tickets or their merchandise - all these things they have to do to make a living. Because, believe you me, they ain't making a living out of recorded music. That's a fact."