The North East Ambulance Service says it is operating under extreme pressure, because of the high number of calls it is receiving.
The operating level has been raised to Level 4, the highest possible measure.
The volume of calls is taking its toll on response times, and the handover of patients at A and E.
While calls to the ambulance service peaked on New Year's Eve, the pressure is still on.
In some circumstances, the service is even asking patients to see whether they have "alternative transport options" - such as a lift from a family member. The trust said it had faced unprecedented demand between Christmas and New Year.
Between 23 December and January 1, it answered more than 40,000 NHS 111 calls and more than 16,000 999 calls - compared to around 28,000 NHS 111 calls and 15,000 999 calls in the same period last year.
The trust said it had even asked workers in urgent care centres whether they can provide additional support.