A Belgian prisoner has been allowed the right to die by a curt in Brussels in a landmark euthanasia case.

A Belgian court has granted a convicted serial rapist and murderer his demand for euthanasia, allowing doctors to carry out the procedure to end his life.

Frank Van Den Bleeken argued that he will never be released from jail, as he is unable to control his violent sexual impulses.

At the end of a three-year legal battle, judges in Brussels have agreed to his request for euthanasia, which he said is the only viable option to end his "unbearable psychic suffering".

"My life has now absolutely no meaning. They may as well put a flower pot here," Van den Bleeken said in a television documentary.

The 50-year-old was jailed almost 30 years ago over a series of rapes he committed in the port city of Antwerp in the 1980s. He also killed one of his victims, a 19-year-old girl.

Van Den Bleeken acknowledges being a "danger to society" and has refused to be considered for early parole saying that there is a great risk he would offend again if let out of jail.

However he has complained that Belgium's lack of adequate therapies for his condition left him without hope.

"If people commit a sexual crime, help them to deal with it," he said. "Just locking them up helps no one: not the person, not society and not the victims."

Such situation caused Van Den Bleeken years of mental anguish, his lawyer Jos Vander Velpen said.

"Over recent years, he has been seen by several doctors and psychologists and their conclusion is that he is suffering, and suffering unbearably," Velpen, told state broadcaster VRT.

Van Den Bleeken first filed a request for euthanasia in 2011.

"I am a human being, and regardless of what I've done, I remain a human being. So, yes, give me euthanasia," he said in the documentary.

He is now to be transferred to a hospital where the medical procedure will be carried out.

Van Den Bleeken's case was the first involving a prisoner and thus the ruling need the consent of the justice ministry.

Belgium became the second country in the world, after its neighbour the Netherlands, to legalise euthanasia for people older than 18 in 2002 and recently extended its right-to-die law to minors.