LONDON, Feb.21 (Xinhua) -- Hospitals in London will be unable to function without doctors and nurses from mainland Europe, the London Assembly's Health Committee has warned in a new report.

The committee has called on government Brexit Secretary David Davis to give greater certainty to health workers from European Union (EU) countries.

Currently there are over 6,000 nurses from the EU working in London's health service.

"The capital's health service is twice as reliant on EU staff as the rest of the country," said the report compiled for the committee.

Reports that the number of EU nurses registering to work in Britain have fallen by 90 percent compared to the year before are alarming, particularly at a time when nursing vacancies have hit an all-time high, the committee report warned.

In a Brexit Directive letter to London Mayor Sadiq Khan, the London Assembly urges him to discuss whether the government could provide a sector-specific guarantee for the rights of EU healthcare workers.

Assembly member Dr Onkar Sahota, chair of the health committee, said: "Many of our hospitals and clinics simply could not function without EU citizens. There are consultants, GPs (family doctors), surgeons and clerical staff from the EU, all working to keep Londoners healthy. EU nurses and doctors are skilled professionals and if they're uncertain about their status in the UK, they leave the NHS."

The London Assembly's EU Exit Working Group heard last year that continued uncertainty is having a significant effect on EU nationals' quality of life and decisions about their future.

An assembly spokesperson said the first phase of the Brexit agreement with the EU was welcomed, adding that it doesn't provide enough reassurance for EU citizens.

"An agreement in principle is not the same as a guarantee," said the spokesperson.