The victim, who remained on ventilator support during most part of her treatment in Safdarjung hospital in Delhi, was brought here in an air ambulance early this morning. A team of doctors and her family members accompanied her.
"The patient arrived at Mount Elizabeth Hospital's Intensive Care Unit this morning in an extremely critical condition," a spokesperson of the hospital said.
"She is being examined and the hospital is working with the Indian High Commission. We request that the privacy of the patient and family be respected," the spokesperson said.
Earlier, the Indian High Commission in Singapore said that the plane carrying the girl landed at the Changi International Airport at 7.30 am (5 am IST).
The decision to shift the girl was taken at the highest level of the Indian government, which has declared that it will bear all the expenses of her treatment.
On December 16, the girl was gangraped and brutally assaulted in a moving bus and thrown out of it in Delhi. She underwent three surgeries but her condition remained critical.
In a statement, the High Commission said that the girl is receiving full medical attention at the hospital.
"We assure all concerned that the patient is receiving full medical attention and the family is also being provided all possible assistance by the High Commission," it said.
The High Commission has also conveyed to the hospital and the family request for privacy of the patient and the family be respected.
"We have received numerous queries regarding the condition of the patient and also many offers to help. We are deeply grateful for all of these offers," the statement said.
"At this stage, we would request that the privacy of the patient, family members as also of the medical team in attendance is fully respected so that the treatment may continue smoothly," the statement added.
In New Delhi, Home Minister Sushilkumar Shinde said the government would spare no effort for the treatment of the victim and it would meet all the costs for her treatment.
"We are all aware of the critical condition of victim. Since the day of the incident, it has been our endeavour to provide her the best of medical care. Despite the best efforts of our doctors, the victim continues to be critical and her fluctuating health remains a big cause of concern to all of us," he said in a statement.
Shinde said when the government was advised by a team of doctors that she may be shifted abroad for treatment, it had ordered India's High Commissioner in Singapore to make necessary arrangements.
"Considering the travel time, the doctors have suggested Mt Elizabeth Hospital, Singapore... Indian doctors have spoken to the doctors of the said hospital and shared the details of the patient," he said.
The minister said arrangements have also been made for the family to stay in Singapore with the patient as the treatment may stretch to many weeks.
Official sources said passport and Singapore visa for the girl and some of her family members who accompanied her were expedited by the External Affairs Ministry.
A meeting of the Union Cabinet presided by Prime Minister Manmohan Singh took the decision to set up a one-person Commission headed by Justice (retd) Usha Mehra to identify lapses and fix responsibility in the girl's case.
Medical Superintendent of the Safdarjung Hospital Dr B D Athani last night said that "the treatment might take longer."
Athani said the girl has suffered severe intestinal and abdominal injuries and more than once she would have to undergo treatment in Singapore which could take several weeks. Parts of the girl's intestine were surgically removed.
"She was being provided the best available aid by a team of specialized doctors. She had to be operated upon thrice."
The victim, whom doctors described as "psychologically composed and optimistic about future", had shown signs of improvement during treatment but her condition worsened in after her pulse rate plummeted for a brief period on Tuesday.
The periodic bouts of infection were also a source of concern for the doctors.