The East of England Ambulance Service, criticised over poor response times, is to take delivery of 120 new vehicles.
The first will go into service in Norfolk, where cover has been described as poor by health watchdogs.
The aim is to have no ambulances over five years old.
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A coroner has ruled Addenbrooke's hospital in Cambridgeshire is not guilty of gross negligence following the death of a Norfolk grandfather
The employee was sorting through rubbish at waste company Amey's Waterbeach facility.
Ice is expected to form on some surfaces from late Tuesday afternoon and last overnight into Wednesday morning.