David Cameron yesterday offered the music industry a unique deal – cut the glorification of materialism, misogyny and guns in hits and the next Conservative government would back an extension of the copyright on sound recordings from the current 50-year period to 70 years.

The change, which must be agreed at a Europe-wide level, means that musicians and singers would be guaranteed to receive royalty payments for their work for most of their lives.

Addressing the British Phonographic Industry annual meeting, Mr Cameron said: “Most people think these are all multimillionaires living in some penthouse flat. The reality is that many of these are low-earning session musicians who will be losing a vital pension.”

Rejecting a report commissioned by Gordon Brown, which said that there was no case for extending copyright, Mr Cameron quoted research which found that the change could boost the music industry by £3.3 billion over the next 50 years.

He argued that extending the term would give an “incentive to the music industry to digitise both older and niche repertoire which more people can enjoy at no extra cost”.

Sir Cliff Richard, The Who and Sir Paul McCartney backed the campaign to extend the 50-year term, as the first rock’n’roll era recordings begin to fall out of copyright.

But in return for the commitment, and a promise that a Tory government would crack down on illegal file-sharing, Mr Cameron said that the music industry must demonstrate a wider social responsibility.

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