The world’s biggest record companies are suing the artificial intelligence song generators Suno and Udio for copyright infringement, alleging that the AI music startups are exploiting the recorded works of artists.

Firms including Sony Music, Universal Music Group and Warner Records say Suno and Udio have committed copyright infringement on an "almost unimaginable scale" in a lawsuit announced by The Recording Industry Association of America on Monday.

One case was filed in the federal court in Boston against Suno AI, and the other in New York against Uncharted Labs, the developer of Udio AI.

The lawsuit claims Suno and Udio’s software steals music to “spit out” similar work and asks for compensation of $150,000 (€140,167) per work infringed.

Suno released its first product last year and claims more than 10 million people have used its tool to make music. The company also partners with Microsoft and charges users a monthly fee.

Udio, known as Uncharted Labs, released its app to the public in April and achieved near-instant fame for being the tool used by US producer Metro Boomin to create ‘BBL Drizzy’ - a parody track about the feud between Kendrick Lamar and Drake.

In the complaints the record labels say the AI firms are simply making money from having copied the songs, when AI firms have in the past argued that their use of the material is legitimate under the fair use doctrine. This allows copyrighted works to be used without a licence under certain conditions, such as for satire and news.

"The use here is far from transformative, as there is no functional purpose for... [the] AI model to ingest the Copyrighted Recordings other than to spit out new, competing music files," the complaints said.

They also said there was nothing about AI that excused the firms from "playing by the rules" and warned that the "wholesale theft" of the recordings threatened "the entire music ecosystem".

Suno AI’s chief executive, Mikey Shulman told The Guardian the technology was “designed to generate completely new outputs, not to memorise and regurgitate pre-existing content” and doesn’t allow users to reference specific artists.

He added that he tried to explain this to labels “but instead of entertaining a good faith discussion, they’ve reverted to their old lawyer-led playbook”.

The lawsuit comes just months after over 200 high-profile musicians have signed an open letter calling for protections against the predatory use of artificial intelligence.