Inpatients at Guy's Hospital in London Bridge and St Thomas' Hospital in Lambeth are no longer allowed to receive visits from family and friends as the NHS continues to deal with the COVID-19 crisis.
Visiting had already been reduced to one person for one hour a day, but from Wednesday all visiting times have been suspended.
"To reduce the spread of infection, we are not currently allowing visitors to adult patients in our hospital or community sites," said Guy's and St Thomas' NHS Foundation Trust on its website.
"Our maternity services are currently restricting visitors to one birth partner.
"This will help us to minimise the number of people in the hospital and reduce the risk of spreading infection to protect our patients and staff."
The trust has confirmed that, to date, five patients being treated at the SE1 hospitals have died after testing positive for COVID-19.
Different visiting arrangements apply to patients at the Evelina London Children's Hospital.
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