The surviving members of the Beastie Boys have vowed not to record new music under the group's name after making a promise to late rapper Adam 'mca' Yauch before his death in 2012.

The hip-hop trio has not released any new material since 2011 album Hot Sauce Committee Part Two, and Michael 'Mike D' Diamond reveals fans won't be hearing anything else from the Beastie Boys now that co-founder Yauch is no longer alive.

He revealed the news during a New York court hearing in the band's ongoing copyright infringement battle against the bosses of Monster Beverage Corp, who stand accused of using five of the band's tracks in a promotional video without permission.

During his testimony on Friday (30May14), Diamond admitted he and Adam 'Ad-Rock' Horovitz had made a vow with Yauch to prevent any new music being released without each member's input.

Testifying at Manhattan Federal Court, the Sabotage hitmaker said, "We have not been able to tour since McA, Adam Yauch, died. We can't make new music."

Diamond returned to the witness stand on Monday (02Jun14), when defence lawyer Dana Susman attempted to depict the band as hypocrites after the rapper claimed they had turned down "a lot of money" after producers behind Arnold Schwarzenegger's recent film Sabotage asked them for permission to use their 1994 song of the same name.

Diamond revealed they had rejected the offer because they "weren't fans of Mr. Schwarzenegger's recent... work", but Susman called the rapper out and suggested they had subsequently backtracked as their song was used as the action man's walk on music during a recent appearance on America's The Tonight Show Starring Jimmy Fallon.

Susman alleged the band had received a fee of $600 (£375) in exchange for allowing a snippet of the track to be used, but Diamond insisted he had no knowledge of the deal and claimed any agreement would have been because they are "fans of that show", reports the New York Daily News.

The Beastie Boys had previously performed on Fallon's previous programme, Late Night with Jimmy Fallon, prior to Yauch's death.