In this case, it seems a flat tyre would have been more acceptable than feeling ill

Ray Carrick, ASU

A meeting of union members also passed a unanimous vote of no confidence in the senior operational management of the Mersey Ambulance Service's northern area.

The ASU represents 160 of the 190 paramedics in the Liverpool and Sefton area which has about 500,000 residents.

Ballot papers have been sent out to all affected staff asking if they are prepared to hold a walk-out and a result is expected in under three weeks.

Ray Carrick, the ASU's general secretary, said: "We are prepared to go this far.

"If the feeling at the meeting was anything to go by, our members will vote to strike over this."

The ambulance stations affected by this action are Southport, Maghull, Old Swan, Formby, Fazakerley, Toxteth, Crosby, Kirkby, South Liverpool, Bootle and Anfield.

'Stomach cramps'

The men currently on suspension are Brian Fullerton and John Sanders, both 41.

Their alleged misconduct took place at the end of their 12-hour shift at 1900 GMT on Thursday.

Mr Fullerton, the driver, said that after dropping a patient off at hospital, he radioed control to tell them he had stomach cramps.

On their way back to Toxteth station, the pair got a call asking them if they were available for a job.

They said they had to stand down from duty because of Mr Fullerton's poor health.

The matter is being handled fully in line with the Trust's agreed procedures

Mersey Regional Ambulance NHS Trust

He was interviewed by managers the next morning and subsequently suspended.

The same action was taken against Mr Sanders when he reported for work the following day.

Ray Carrick, the ASU's general secretary, said: "There is nothing unusual or unique about paramedics having to stand down from duty because of sickness.

"In this case, it seems a flat tyre would have been more acceptable than feeling ill."

Mr Carrick claimed no patient is involved in the allegations, because after the call was passed on to the next station no ambulance was needed.

A spokeswoman for the Mersey Regional Ambulance NHS Trust, said: "The Trust can confirm two members of staff have been suspended while a thorough investigation takes place into the causes of the alleged incident.

National strike

"The matter is being handled fully in line with the Trust's agreed procedures."

The biggest strike by ambulance crews in the UK was a national dispute over pay which escalated over two months in 1989.

Army ambulances and police vehicles were brought in across the country.

Mr Carrick said: "If we go ahead with the strike, I believe it would become necessary to use police vehicles in Liverpool and Sefton."