The car used in the terror attack on Westminster Bridge was hired from a branch of Enterprise in Birmingham.
A man mounted the pavement on Westminster Bridge and drove the Hyundai through a crowd of people, including schoolchildren.
He was then shot dead by armed officers in the courtyard outside the Houses of Parliament after he stabbed PC Keith Palmer, who died of his wounds.
A spokesperson for Enterprise Holdings said: “We can confirm that the car used in the tragic attack in London yesterday afternoon was one of ours.
"An employee identified the vehicle after seeing the licence plate in an image online. We ran another check to verify, and immediately contacted the authorities."
They added: "We are co-operating fully with the authorities and will provide any assistance that we can to the investigation.
"Our thoughts are very much with the victims of this terrible tragedy.”
Earlier, the BBC reported the car had been hired from Solihull, however the Enterprise spokesperson confirmed this was not the case.
"We are not releasing any further details," the spokesperson said.
