Mutilation is to strong a word.
It cannot be classed as mutilation, because a body part is not permanately removed, only skin, which as others have said can be done for medical reasons and does not impare function.
The procedure, if done properly does not cause death, long term pain and problem, as FGM does, even if done by doctors. So that is why comparing them is not helpful.
If this law is implemented in the UK then it will drive circumcision under ground and may stop parents taking medical advice, if it looks like the child is developing problems.