The 23-year-old gang-rape victim continues to be serious and critical but is conscious and talking, a week after the brutal attack on her in a moving bus in south Delhi.

Doctors attending on her at the Safdarjung Hospital said she underwent a "small" surgery for abdominal wash and would be put on ventilator so that her condition improves.

"We will put her on ventilator electively. We think this will improve the health condition...Infection is a serious concern and she continues to be serious but communicating and concious.

"She is critical and still in ICU. We need to watch her for the next few days," Dr B D Athani, Medical Superintendent of Safdurjung Hospital, told reporters on Sunday evening.

The victim, a para-medical student who is battling for life at Safdurjung Hospital here, was off ventilator since Friday but due to some respiratory problems she was put on ventilator again this evening.

"We are subjecting her to all examinations and procedures. She continues to be critical," Athani said.

The girl's family members said she was put on ventilator in the evening after doctors diagnosed "some problem".

Doctors had said on Saturday that the rape victim is psychologically "composed and optimistic" about her future and has started communicating.