A seriously ill baby whose parents are divided over whether he should be allowed to die has shown signs that he likes music and can tentatively bang a drum, the High Court in London heard Friday.

The estranged parents of the one-year-old boy, known only as Baby RB, are locked in a legal battle over his doctors' request to turn off the ventilator that has helped him breathe since he was born last October.

His mother backs the doctors, saying he deserves not to suffer any more, but his father insists he can hear, see and feel.

A senior nurse in Baby RB's intensive care unit told the court that despite being largely immobile due to a rare neuromuscular condition, he has been seen to make "purposeful movements" and respond to being cuddled by his parents.

He said nurses had reported changes in the boy's behaviour in the past few months, in the form of more interaction with his surroundings.

- If you place a toy in his hand, he will move the toy. He certainly appears to like music. If you place a stick in his hand, he will bang the drum - said the nurse. No one in the case can be identified for legal reasons.

Baby RB has a rare neuromuscular condition which severely limits his ability to breathe and move his limbs.

His doctors want his life-supporting ventilator to be withdrawn so that, with palliative care, he can die in peace rather than continuing to live a "miserable and pitiful existence".

The case continues.