The court said the matter will come up for hearing in the regular list.
The Delhi High Court Tuesday sought the response of MLA and gangster-turned-politician Mukhtar Ansari and six others, who were acquitted in the 2005 murder case of BJP leader Krishnanand Rai, on a plea filed by the wife of the victim.
A bench of Justices Manmohan and Sangita Dhingra Sehgal admitted the appeal of Alka Rai and issued a notice to the persons acquitted in the case.
The court said the matter will come up for hearing in the regular list.
The CBI had also approached the high court last week against the acquittals of the accused.
The trial of the 2005 murder case was transferred from Ghazipur in Uttar Pradesh to Delhi by the Supreme Court in 2013 on a plea filed by Alka Rai.
Krishnanand Rai was a member of the Uttar Pradesh Legislative Assembly, representing the Mohammadabad constituency from 2002 to 2007.
He was killed on November 29, 2005, along with six others.
Ansari, the MLA from Mau in Uttar Pradesh, has several criminal cases against him, including that of murder and abduction.
The trial court here had acquitted the accused in July this year on the ground that all the eyewitnesses and material witnesses had turned hostile.
It said that had the prosecution witnesses not turned hostile, the outcome of the trial would have been different and highlighted the absence of a witness protection scheme during the trial.
Earlier, the Allahabad High Court had directed a CBI inquiry into Rai's killing.
Challenging the high court order, the Uttar Pradesh government had moved the Supreme Court, which refused to allow its plea saying the case deserved to be probed by the country's premier investigating agency.
Besides Mr Ansari, the trial court had also acquitted his brother Afzal Ansari, Azaz-Ul-Haq, Sanjeev Maheshwari, Rakesh Pandey, Ramu Mallah and Mansoor Ansari.
It had held that the investigators failed to prove the charges by not bringing enough evidence against the accused persons who were allegedly responsible for the gruesome killing of seven persons, including Rai.
"This is a gruesome case involving the murder of seven persons. The investigation of the case was transferred from UP Police to CBI. The trial of the case was also transferred from UP to Delhi. Unfortunately, the case of the prosecution has suffered as all the eyewitnesses and other material witnesses turned hostile.
"The case in hand is another example of the prosecution failing due to hostile witnesses. If the witnesses, in this case, had the benefit of the Witness Protection Scheme, 2018 during the trial, the result may have been different," it had said.