Taylor Swift has been criticized for releasing her back catalog on streaming services on the same day as her pop rival Katy Perry's new album release.

The Blank Space singer pulled her music from Spotify in 2014 after disagreeing with their policy on music royalties but her absence across most streaming sites came to an end at the turn of midnight on Friday (09Jun17) to celebrate her album 1989 selling 10 million albums worldwide.

However, that meant her music was released at the same time as Witness, the new album by Katy, who Taylor fell out with over backing dancers for their tours, and many took to Twitter to brand Taylor as "immature" over the timing of her return to streaming.

"I think we all can agree Taylor Swift is the most immature artist of all time," one user posted, while another wrote, "Seeing @taylorswift13 back on Spotify the day @katyperry's new album comes out is the most immature thing you can do as an ADULT #growup."

Singer Lily Allen also chipped in, retweeting the release news and adding, "In other news, mean."

"Taylor Swift said she hates Spotify. Now her musics on Spotify... coincidentally the same day as Katy Perry drop Witness... ALL SHADE (sic)," a user contributed, and another added, "Taylor Swift putting her entire discography on Spotify the same night Katy Perry drops a new album is next level pettiness & I am all for it."

Another account accused Taylor of stealing Katy's thunder by writing, "taylor swift's the kind of person who'd go into labor at someone else's baby shower or announce her engagement during someone else's wedding."

Taylor wrote the song Bad Blood about their feud but has never directly addressed rumors it was about Katy. However, the Roar singer recently opened up about it during an episode of Carpool Karaoke with chat show host James Corden, saying she tried to reach out to Taylor and make amends but it was "a full shut down".

In this week's edition of Britain's NME magazine she talked about the drama again, saying, "I wish that I could turn the other cheek every single time, but I'm also not a pushover, you know? Especially when someone tries to assassinate my character with little girls. That's so messed up!"