The famous scientist Stephen Hawking has said he backs the notion of assisted suicide for people with terminal illnesses. What is Islam’s view?

Famous cosmologist Prof Stephen Hawking has said he backs the notion of assisted suicide for people with terminal illnesses.
In an interview with BBC his argument was : "We don't let animals suffer, so why humans?"
Should we see this as suicide or murder. can this action be justified? I want to know your point of view on this.

If the patient is conscious and he consciously decides to commit suicide for the sake of relief from pain, then this kind of practice is haram in Islam. But, another case is that the patient is living just like a plant with the aid of the life support system, and the doctor decides to remove this system because the patient cannot be revived any further. If the patient automatically dies on the removal of this system, then this will not be suicide.