A doctor who administered a massive dose of a paralysing drug to two terminally-ill babies - hastening their deaths - told medical watchdogs yesterday how he "felt in his heart" the children were suffering.

Consultant neonatologist Michael Munro, 41, injected the two children, known only as babies X and Y, with muscle relaxant Pancuronium after they suffered violent body spasms in the moments before their deaths.

He explained how the phenomenon, known as agonal gasping, was "horrendous to witness" for the families of both children. Dr Munro, of Aberdeen, was working at the city's maternity hospital in 2005 when both babies were admitted.

The General Medical Council's fitness to practise panel, sitting in Manchester, was earlier told the doctor's decision to administer the drug was contrary to guidelines and "tantamount to euthanasia".

The doctor denies an allegation that his fitness to practise is impaired by reason of misconduct. The hearing was told baby Y was born on June 20, 2005, two weeks premature, and baby X was born on December 5, the same year, more than three months early.

Both children suffered complications during pregnancy with baby X suffering a serious brain haemorrhage and baby Y born with pulmonary hypoplasia and pulmonary hypertension. Giving evidence at the beginning of his defence, Dr Munro described the final moments in the life of baby Y.

He told how the decision was taken for treatment to be withdrawn and the infant was given to his parents. The child's breathing faded, and a nurse and the family believed the infant had died.

Dr Munro returned to the baby to certify death and found its heart was beating faintly. He said: "Baby started agonal gasping. I think this is horrendous to witness. Baby then started to build on this agonal gasping - that is to say it increased in frequency. I believe the baby appeared very distressed."

Asked how the parents of baby Y appeared, Dr Munro replied: "They were utterly distraught. If you put yourself in their shoes, they have already said their last goodbyes to their baby, then suddenly there are these massive, racking agonal gasps which appeared to build up - they were utterly, utterly distraught.

"The parents were in tears saying things like I can't take any more'. I took the decision to administer Pancuronium."

"While the nurse was outside, I explained to the parents this drug was to be used to ease the suffering but one of the consequences of its use might be to hasten death. They were happy with that."

Questioned about why he failed to record the drug's use in medical notes, Dr Munro denied he had attempted to hide his actions.

In the case of baby X, the doctor was again called to certify death and discovered the infant's faint heartbeat.

Again the child began agonal gasping. Dr Munro said: "I tried to explain that this was simply a reflex although I felt in my heart that this baby was distressed."

Following discussion with the child's family, Dr Munro made the decision to administer a dose of Pancuronium and the infant died a short while later. He again denied his failure to record the use of the drug in notes was an attempt to hide his actions but conceded his note-taking had been inadequate.

Following an application by Dr Munro's lawyer, Michael Mylonas, a number of the charges against the doctor were dropped yesterday morning.The hearing was adjourned until today.