The London Ambulance Service says it will be under “significant pressure” next week when staff stage a walk-out Monday in a national dispute over pay.
Staff are also due to hold further industrial action – including refusing to work overtime – during the rest of the week.
Bosses say services will be disrupted throughout the week and warn that on Monday many patients will not be allocated an ambulance.
While those with life-threatening conditions will still get an ambulance response, those with minor breaks and injuries, women in routine labour and those involved in minor road traffic accidents will be given clinical advice, provided with alternative transport or told to make their own way to hospital.
Director of Operations Jason Killens said: “We are expecting a significant number of our staff to take four hours of strike action on Monday between 7am and 11am.
“We have plans in place to ensure we reach the most seriously ill and injured patients as quickly as possible. These include all clinical managers working on the front line, the use of more private ambulance crews and support from other emergency services.
“However, people who need an ambulance response, but are not in a life-threatening situation, should expect to wait longer or may not get an ambulance at all.”