The attack sparked a wave of protests across India in which a police officer died and more than 100 police and protestors were injured.
The 23-year-old victim has already undergone three operations in India after suffering severe intestinal injuries during the 40-minute gang rape on December 16 in which she was also assaulted with an iron rod.
She was flown by air ambulance from New Delhi overnight and arrived at Singapore's Mount Elizabeth Hospital early on Thursday "in an extremely critical condition", the hospital said in a statement.
"She is being examined and the hospital is working with the Indian High Commission [embassy]," it said, adding she was being treated at its intensive care unit.The head of the hospital that treated her in New Delhi hinted that the Mount Elizabeth Hospital, located in Singapore's Orchard Road shopping district, was chosen for its modern organ transplant facility.
"The said hospital has a state-of-art multi-organ transplant facility. The arrangement has also been made for the family to accompany her as the treatment may take longer period," BD Athani, medical superintendent of Safdarjung Hospital in Delhi, said on Wednesday.
"She has had to be operated upon three times. With fortitude and courage she has survived the after-effects of the injuries so far but her condition continues to be critical," he told reporters.
Government to cover the cost
The decision to approve the 23-year-old's transfer was taken at a Cabinet meeting in New Delhi on Wednesday and authorities said the Indian government would cover the cost of medical treatment.
"We arranged the passport and visa for the victim and members of her family," a foreign ministry official said.
India said it was setting up a special commission of inquiry after the gang rape which occurred when the woman was allegedly tricked into boarding a bus by six men who then took turns to assault her.
Six suspects have been arrested in connection with the attack and have been remanded in custody.
Announcing the commission on Wednesday, Finance Minister P Chidambaram said a separate panel would examine existing legislation and "suggest changes in the laws in order to make punishment for such horrific crimes stiffer".
"Whatever we do now is intended to demonstrate the government's serious intent in the matter that we will apprehend and punish the perpetrators. We will try and find out what went wrong … and fix responsibility and amend the laws," he said.
Thousands of people have taken to the streets since the attack to demonstrate both against the levels of violence and also the notoriously slow criminal justice system. – AFP