Delhi Police, through its standing counsel Varun Goswami, has also challenged the acquittal of 10 other co-accused in the matter.
A bench of justices Sanjiv Khanna and Ashutosh Kumar is likely to hear the matter tomorrow.
The trial court had on August 8, 2014 convicted 35-year-old Rana while acquitting the 10 other co-accused in the case.
Rana, who was awarded life term on August 14 last year, was held guilty of offences under sections 302 (murder), 307 (attempt to murder) and 34 (common intention) under IPC in the case. However, the accused were acquitted of the charges under section 120B (criminal conspiracy) of IPC.
It had also observed that facts of the case does not fall into the category of rarest of rare warranting death penalty as the motive behind the murder could not be established.
37-year-old Phoolan, then a Samajwadi Party MP from Mirzapur constituency in Uttar Pradesh, was shot dead from close range by three masked gunmen in front of her Ashoka Road residence here in the heart of the capital's VIP area as she returned home for lunch after attending Lok Sabha session on July 25, 2001.