Gandhi, in her first public reaction on the incident, skipped wishing New Year greetings, saying "...Not so today because our thoughts are with the young woman, who is fighting for her life after the barbarous attack".
She added "our only wish today is that she recovers and comes back to us and that no time is lost in bringing the perpetrators of such a barbarous act to justice".
Gandhi was responding to questions after unfurling the party flag at the AICC headquarters to mark the completion of 127 years of the since its formation.
The Prime Minister, who stood by her side, also addressed the media saying, "We share the anguish and the anger of the country over this heinous crime".
Describing the victim, who is currently under treatment in a hospital in Singapore, as a "brave young girl", Singh said that best possible medical care is being provided to her.
"Our prayers are with the brave young girl," he said.
Singh pointed out that the government has constituted two committees under Justice J S Verma and Justice Usha Mehra to to suggest ways and means of modification in laws related to crimes against women and to look into lapses on anybody's part in dealing with the aftermath of this crisis respectively.
"So you have my assurance that our government is committed to bringing the guilty to justice as soon as possible," the Prime Minister said.
Gandhi also held a meeting at the party headquarters with Singh, senior ministers and leaders including Home Minister Sushil Kumar Shinde and Delhi Chief Minister Shiela Dikshit, where the issue is learnt to have come up.
Rahul Gandhi was not present during programme. Shinde was seen talking to Dikshit for long during the ceremony.
The gangrape issue was earlier raised prominently at the Congress Core Group meeting chaired by Gandhi and attended by the Prime Minister on Tuesday during which the Congress President is learnt to have said that there is a need for police to address the issue with greater sensitivity.
During the meeting, the Home Minister had given a detailed briefing of the steps being taken by the government to enhance security in the city after the incident as well as the action taken so far in the gangrape case.
The 23-year-old gang-rape victim, battling for life at Safdarjung Hosptial where she was admitted on December 16, was shifted to the super specialty Mount Elizabeth Hospital in Singapore on December
The victim was gangraped and brutally assaulted in a moving bus and thrown out in south Delhi.