London's directly elected mayor, Boris Johnson, should be handed formal oversight of the capital's ambulance service to ensure it works more closely with other emergency and transport services, a new report has suggested.

The study, published by the London Assembly on 16 December, notes that the London Ambulance Service (LAS) is the busiest in the country, fielding 1.5 million '999' calls a year. Yet the service, like many public organisations, has been asked to cut its budget and staffing levels while demand is rising.