The song, entitled "I Would Take the Pain Away," and a five-minute video of clips and photographs of Benazir Bhutto has been broadcast on the state-run Pakistani television and posted on the video-sharing website YouTube.

"My mother was murdered. I don't even comprehend. Was it worth dying for? I'm walking through screened doors," Bakhtawar, 18, sings in English on the lilting hip-hop song.

"No comfort or ease. I'm begging you please God bless the deceased," Bakhtawar sings.

Information Minister Sherry Rehman, for years an aide to Bhutto, said Bakhtawar, a student at Britain's Edinburgh University, wrote the lyrics and music.

"It's a tribute of a grieving daughter to her iconic and loving mother," Rehman told Reuters on Monday.

Music was a hobby for Bakhtawar and she had no plan to pursue it as a career, Rehman said.

Bhutto, 54, was murdered in a suicide gun-and-bomb attack in the city of Rawalpindi in December 2007. The then government, led by former president Pervez Musharraf, blamed the attack on Islamist militants.

Bhutto's widower and Bakhtawar's father, Asif Ali Zardari, become president in September.

Their son, Bilawal, 20, studies at Oxford University in Britain and another daughter, Aseefa, 15, also studies abroad.