Pop star Ke$Ha has debuted her new single by belting it out for unsuspecting passengers on a busy subway in Tokyo, Japan.

The TiK ToK hitmaker has uploaded footage of herself singing the chorus of Die Young to video-sharing website YouTube.com.

In the black-and-white preview, Ke$ha can be seen riding alongside Japanese commuters in a silent train carriage when she suddenly stuns them all - and even wakes up one sleeping businessman - by performing her track a cappella.

She continues to sing along to her music player, oblivious to the passengers glaring at her.

Sharing the video on her Twitter.com page, the star writes, "Animals (fans)! You heard it here first... Getting closer. Get hyped..."