"Till the World Ends" is a song by American recording artist Britney Spears. It was released as the second single from her seventh studio album, Femme Fatale. "Till the World Ends" was written by Dr. Luke, Alexander Kronlund, Max Martin and Kesha, while being produced by Dr. Luke, Max Martin and Billboard. The main inspiration of the song for Kesha was imagining Spears and any other female musician touring the world. "Till the World Ends" was leaked on March 3, 2011, and was released for digital download the following day. The song is composed as an uptempo dance-pop and electropop song with a chant-like chorus, where Spears sings about dancing until the end of the world. Mathew Knowles and Beyoncé expressed interest towards the song in December 2010, but was denied access by Spears' label, Jive Records.

Read this from some forum:

"Beyonce is so pressed that Mathew wasn’t able to buy her “Till the World Ends” and “I Wanna Go” from Sony. mathew Knowles was negotiating that the songs should be sent to Beyonce, but Sony stopped them from getting being sent to Columbia.

Rumor has it that Beyonce wanted to write a few words and claim songwriting credit for Till the World Ends, but the songwriters protested about her scheming. She fired Mathew because he can’t license the pop-dance songs she wanted to plagiarize!

Even Dr. Luke tweeted that she wanted to steal the Britney songs and attach her name to it!"

Beyonce wants britney's songs! Oh my god!