The case of an elderly woman with a broken hip waiting for an ambulance for two hours is just the tip of the iceberg, the ambulance union says.

It has warned that if under resourcing is not addressed, ambulance drivers could soon be taking industrial action.

Eighty-one-year-old Irene Derby fell and broke her hip at her Elizabeth North home earlier this week and was forced to wait for two hours for an ambulance to arrive.

Phil Palmer from the Ambulance Drivers’ Union says drivers are put in that situation all too often.

“The ambulance service is seriously under resourced,” Mr Palmer said.

“There’s not enough emergency crews to do the job, and we’re going to be hearing more and more of this.”

Mr Palmer said Mrs Derby’s case is not an isolated incident, with an ambulance from Ashford Hospital recently being sent to attend an emergency at Elizabeth, 30km away.

“If they can’t get to patients on time and if the government won’t do anything about it, then we’ll take industrial action, it will be this year and it will be over the next few months," he said.