“Deeply saddened to hear of the death of Andreea Cristea. Londoners hold her and her loved ones in our thoughts today,” said mayor of London Sadiq Khan
The 31-year-old had been receiving urgent medical care in hospital after she was injured in the 22 March attack. Her life support was withdrawn yesterday afternoon.
Police named the woman as Andreea Cristea, a Romanian national visiting London when Khalid Masood, 52, drove a car into crowds on Westminster bridge.
Ms Cristea, an architect who was in the capital with her boyfriend Andrei Burnaz to celebrate his birthday, fell into the Thames during the attack.
It is not clear whether she leapt into the water to escape the violence or if she was thrown from the bridge as part of it.
“After fighting for her life for over two weeks, our beloved and irreplaceable Andreea – wonderful daughter, sister, partner, dedicated friend and the most unique and life loving person you can imagine – was cruelly and brutally ripped away from our lives in the most heartless and spiritless way,” said Ms Cristea’s family in a statement.
“She will always be remembered as our shining ray of light that will forever keep on shining in our hearts.”
The attacker stabbed a policeman, named as PC Keith Palmer, to death before being shot dead himself.
US tourist Kurt Cochran, retired window cleaner Leslie Rhodes and Aysha Frade, who worked at a London sixth-form college, also died when Masood drove his car into people walking across the bridge.
Ms Cristea’s family said they would like money donated to her recovery to be given to charity.
Mr Burnaz suffered a broken foot during the attack but has since left hospital. The Romanian ambassador to the UK, Dan Mihalache, has said Mr Burnaz had planned to propose to Ms Cristea on the day of the attack.