The New South Wales Health Minister has apologised to an elderly woman who fell on a footpath and had to wait there for hours before an ambulance came.

The 83-year-old woman was on the ground outside her home in Sydney for two-and-a-half hours before she could be moved, reports say.

The NSW ambulance service says it has extended a deep apology to the woman, and it is reviewing the incident, but pointed out that paramedics were under serious pressures due to of a spike in winter-related illnesses.

NSW Health Minister Jillian Skinner said she wanted an explanation.

“Two-and-a-half hours after they were called - I believe that is totally unacceptable and I have extended my deepest sympathy to the patient and to those people who were with her for this delay,” the Minister told reporters.

“What else was happening that prevented paramedics from getting to her?

“I've asked the acting chief executive of NSW Ambulance for an explanation as to how this could have happened.”

Ms Skinner is aware of the spike in presentations at hospitals, but said that was not enough of an excuse.

“At this time of the year there always is [a spike],” she said.

“But of course we've been warned about a particular flu and we have to accommodate that.”

“It is, I believe, something to do with bed block, where we have more patients than expected needing to be admitted to hospital for treatment.”