Ludwig Minelli, has told the BBC that suicide is a "marvellous possibility".
The founder of Swiss right-to-die organisation Dignitas has defended helping Britons, including some psychiatric patients, kill themselves.
Ludwig Minelli told the BBC suicide was a "marvellous possibility" and he wants the assisted suicide law clarified for the healthy partners of dying people.
Former Labour Health Secretary Patricia Hewitt said his comments showed the need for a change in UK laws.
More than 100 Britons, mostly terminally ill, have died at Dignitas.
In his first broadcast interview for five years, Mr Minelli told BBC Radio 4's The Report that failed suicide attempts created problems and heavy costs for the UK's National Health Service.
He said: "I have a totally different attitude to suicide. I say suicide is a marvellous marvellous possibility given to a human being."
He added: "Suicide is a very good possibility to escape a situation which you can't alter."
Mr Minelli said: "It is not a condition to have a terminal illness. Terminal illness is a British obsession.
"We are not a clinic. As a human rights lawyer I am opposed to the idea of paternalism. We do not make decisions for other people."
And Mr Minelli revealed that his organisation plans to test the legality of assisting the suicide of a healthy woman whose partner is terminally ill.
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"There is a couple living in Canada, the husband is ill, his partner is not ill but she told us here in my living room that 'if my husband goes, I would go at the same time with him'.
"We will now probably go to the courts in order to clear this question."
Dignitas is known in Britain for having helped more than 100 people to kill themselves.
The majority were terminally ill, but there have been more controversial cases such as psychiatric patients and couples, even when one was less ill than the other.
Suicide assistant Soraya Wernli said she resigned from Dignitas because she was concerned at the way couples and mentally ill people were dealt with by the organisation.
"I have no problem at all with assisted suicide, if somebody is terminally ill, my problem is with how Dignitas deals with it," she said.
Dignitas has also been criticised for helping Daniel James, aged 23, to commit suicide last year after he was paralysed while playing rugby.
Marjorie Wallace, chief executive of mental health charity SANE, said Mr Minelli was offering "a seductive but dangerous solution to the feelings of anguish and hopelessness experienced by some people with mental illness".
Suicide assistant Soraya Wernli resigned from Dignitas
She said they should have greater access to effective treatment, rather than the "one-way ticket to despair and unnecessary death" offered by Dignitas.
Last month, Patricia Hewitt tabled an amendment to the Coroners and Justice Bill which would have guaranteed protection from prosecution in England and Wales for relatives and friends who accompany people travelling abroad to kill themselves.
The amendment was not voted on.
But asked whether she was aware that people with mental illnesses were able to commit suicide at Dignitas without being seen by a psychiatrist in Switzerland, Ms Hewitt said: "I don't think that would be an adequate safeguard for somebody suffering from a psychiatric illness.
"That's why it would be much better to have a British law on this issue."
Swiss authorities are reviewing their assisted suicide law, which could make it more difficult for people to travel to the country to commit suicide.
Its main medical ethics commission has drawn up a long list of recommendations, including longer assessments, and tougher appraisals of psychiatric patients wishing to kill themselves, and of couples in apparent suicide pacts.
The commission's President, Christoph Rehman Sutter, told the BBC that Switzerland's law consists of one sentence in the penal code that says assisted suicide is a crime if it is done for self-seeking motives.
"We have this very strange situation of having a practice without regulation," he said. "There is no regulation at the moment."
Switzerland's Justice Ministry told the BBC it is will put forward proposals for reform within the next two months.
The Report broadcasts on BBC Radio 4 on Thursday 2 April at 2000 BST. You can also listen via the BBC iPlayeror download the
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