Paul McCartney and U2  were among thousands of musicians who signed a full-page newspaper ad that appeared Thursday, calling on the British government to extend copyright protection for their work.

Peter Gabriel, Cliff Richard and Billy Bragg were also among the 4,000 performers whose names appeared in the Financial Times pages calling for an extension, a position that also has the support of most record companies.

"We call upon the U.K. government to support the extension of copyright in sound recordings," the ad read.

The appeal was in response to Wednesday's release of the Review of Intellectual Property, which was commissioned by Britain's Treasury. The review was led by Andrew Gowers, the former editor of the Times.

Gowers's report rejected calls by the British Phonographic Industry (BPI) to extend Britain's copyright on sound recordings to 95 years, from the current 50 years.

Those terms would compare to the Sonny Bono Act, enacted in 1998 to lengthen copyright protection in the U.S.

Gowers argued in the report that there must be a balance between protection of the artist and of the consumer, and he rejected the notion that artists would move elsewhere to evade the shorter copyright protections.

It's not known whether the government will act on the recommendation. If so, recordings by artists such as Richard, the Beatles and the Rolling Stones would be in the public domain within the next few years.

The Open Rights Group, which included Matt Black, a DJ from Coldcut, supported Gowers's recommendation.

"The only people to benefit from term extension would be the giant traditional media groups," Black said.

"Here we can recognize that music is a key part of our culture, [and, indeed, a key export], that recycling is a natural part of musical creativity," he added.

The review also called for a crackdown on music piracy and counterfeiting operations, including dramatically increasing the maximum prison sentences for those found guilty of online copyright infringement to 10 years from two.