London (CNN) Nine London bus drivers have died from the coronavirus along with five other transport workers, as demands grow for better personal protection for transport employees in the UK capital.

London Mayor Sadiq Khan said Wednesday that he is working with the transport authority TfL, bus operators and unions to protect workers and passengers through new measures . These include enhanced cleaning, providing protective film for drivers' screens, and boosting social distancing on buses and at stops.

The UK is still grappling with a surge in Covid-19 cases, with the country reporting its highest single-day death toll of 938 on Wednesday, bringing it to a total of 7,097 deaths and 60,733 cases, according to its Department of Health and Social Care.

Prime Minister Boris Johnson, who is suffering from coronavirus symptoms, spent a second night in intensive care on Tuesday amid warnings that the high point of infections is yet to come.

"I speak to experts regularly. We think the peak -- which is the worst part of the virus -- is still probably a week-and-a-half away," Khan told BBC radio on Wednesday.

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