Iggy Azalea takes aim at Britney Spears on Twitter

WASHINGTON, June 30 (UPI) -- Australian rapper Iggy Azalea, 24 is off on another Twitter rant. This time the "Fancy" singer is taking aim at the queen of pop Britney Spears, 33.

After working together on "Pretty Girls," Azalea took aim at Spears on the social media site while answering fan questions. Azalea claiming Spears was the reason their pop song failed to do better.

Azalea, who felt they should have promoted the single more, said it was a flop after it only made 29 on the Billboard charts.

The rapper recently cancelled her Great Escape tour, saying she was in need of a mental break, according to the Sydney Morning Herald. Rumors have been circulating the real reason for the cancellation was her inability to secure an opening act, reports the Washington Post.

Spears, on the other hand, just extended her residency at Planet Hollywood in Las Vegas and was recently named one of Forbes highest paid celebrities. The singer shot back at Azalea, saying: "Can't wait to get back to Vegas. So thankful I have shows for the rest of the year to look forward to... #YouWantAPieceOfMe."

Despite the jab, Azalea did not back down on Twitter, stating, "You need content to compete in 2015" and blamed the fact that she was only featured on the song and there was no promotion for the single.

Azalea tweeted that the two remain genuine friends after it all, though Spears may not feel the same.