Justice Minister Carlo Nordio made the demand to Pakistani authorities on Tuesday.
The trial into the murder of Saman Abbas began on February 10 in Reggio Emilia.
Her uncle, Danish Hasnain, and two cousins, Ikram Ijaz and Nomanhulaq Nomanhulaq, are in the dock, while her father, Shabbir Abbas, and mother, Nazia Shaheen, have also been indicted.
The father's extradition from Pakistan has been held up while the mother is still a fugitive from Italian justice in the south Asian country.
Saman's boyfriend, Saqib Ayub, is standing as civil plaintiff in the trial.
Ayub wants justice to be done for his late girlfriend and will use any damages from the proceedings to set up a foundation against 'honour killing' and to help victims of forced marriages in her name, his lawyer Claudio Falleti told QB-Il Resto del Carlino newspaper.
Falleti called the delays in the extradition process "unacceptable".
On January 31 this year, Hasnain, accused by his nephew, Saman's brother, of strangling her, said that he did not commit the act, but did accompany the young woman's two cousins, Nomanhulaq and Ijaz, to bury her body together near the family home at Novellara near Reggio Emilia, according to judicial sources.
On November 18 last year, Hasnain had guided police to the place near the family home where they buried Abbas after 18 months of vain searches, including with sniffer dogs.
Hasnain reportedly told police her cousins blamed the mother for the murder but he did not believe she'd committed the murder, either.
On January 4, Saman's body was ID'd from her teeth, a lawyer for the Penelope missing persons and women's rights group who is also a civil plaintiff in the trial, said.
The lawyer, Barbara Iannucelli, said a bone in Abbas's neck had been broken and further examination has been required to establish if this injury was inflicted pre- or post-mortem.
The fracture of the bone in the front of the neck would support the hypothesis that she was strangled by Hasnain, as he has been charged.
The alleged 'honour killing" was perpetrated, police said, because of Saman's refusal to marry the older man in Pakistan and also because the family objected to the western-style life she was living with her boyfriend, Ayub.
Saman had taken refuge in a women's shelter but her mother lured her back to be killed, police say, by promising her that they would let her live as she wanted.
ANSA
