Performing Rights Society for Music (PRS) says it will pursue SoundCloud "through the courts" for unpaid royalties.

In a letter to its members, PRS says that SoundCloud needs a licence to operate in the UK and Europe.

It added that it has asked the streaming site "numerous times to recognise their responsibilities".

SoundCloud has told Newsbeat the legal action is "regrettable".

In a press release, PRS added that it had "no choice" but to take legal action after five years of "unsuccessful negotiations".

"We asked them to take a licence to cover the use of all our members' repertoire or otherwise stop infringing."

PRS also said that it sent SoundCloud a list of 4,500 musical works as a sample of what was on the site and said "we understand SoundCloud has taken down some of our members' works from their service".

"SoundCloud decided to respond to our claim by informing us that it had removed 250 posts.

"Unfortunately, we have no visibility or clarity on SoundCloud's approach to removing works, so it is not currently clear why these particular posts have been selected by them given the wider issue of infringement that is occurring.

"Ultimately, it is SoundCloud's decision as to whether it starts paying for the ongoing use of our members' music or stops using these works entirely."

Bloomberg magazine published an article last year saying that SoundCloud had entered into negotiations with major labels over royalties.

The site has also turned on an automatic content identification system, as it says on its site, to be "used primarily for identifying audio that rights holders have requested to be taken off SoundCloud."

But in a statement, SoundCloud said: "It is regrettable that PRS appears to be following this course of action in the midst of an active commercial negotiation with SoundCloud.

"We believe this approach does not serve the best interests of any of the parties involved, in particular the members of the PRS, many of whom are active users of our platform and who rely on it to share their work and communicate with their fan base."

The statement added: "SoundCloud is a platform by creators, for creators. No one in the world is doing more to enable creators to build and connect with their audience while protecting the rights of creators, including PRS members.

"We are working hard to create a platform where all creators can be paid for their work, and already have deals in place with thousands of copyright owners, including record labels, publishers and independent artists."

Follow @BBCNewsbeat on Twitter, BBCNewsbeat on Instagram, Radio1Newsbeat on YouTube and you can now follow BBC_Newsbeat on Snapchat