David Goodall, a 104-year-old Australian scientist who had campaigned for the legalisation of assisted dying in his home country, ended his life at a Swiss clinic on Thursday, a representative from the pro-euthanasia group Exit International said.

Goodall, a respected botanist and ecologist, died at the Life Circle clinic in Basel, Switzerland, after administering a lethal drug under the guidance of doctors, ABC News Australia reported. Exit International, which represented the scientist, said Goodall passed away while listening to Beethoven's "Ode to Joy". Euthanasia is illegal in Australia, thought the state of Victoria is planning to allow assisted dying from mid-2019. Goodall's home state Perth is currently debating whether to introduce the policy.

The story of the academic, who is one of the first Australians to undertake the procedure due to old age rather than a terminal illness, attracted international headlines and further inflamed a highly divisive debate. His supporters applauded his decision to take charge of his fate after declaring his life was no longer worth living. But critics warned his decision solely on the grounds of old age set a "dangerous precedent".

The grandfather of 12 had attracted over $20,000 in donations from the public to help fund his journey to Europe from Australia earlier this month. Earlier this week, Goodall said he resented having to travel so far to carry out his plan, but was relieved the end was near. "Life stopped being enjoyable five or 10 years ago," he said, in part because of his failing mobility and eyesight. "I am glad to arrive (in Basel). I'll be even more pleased when further steps of my journey are completed. I have been able to say goodbye. I was a bit sorry to say goodbye to my family in Bordeaux but that's the way it was."

Goodall said he hoped his story would lead to the legalisation of assisted dying in other countries. "I'm looking forward to it," he said of his imminent death. "What I would like is for other countries to follow Switzerland's lead and make these facilities available to all clients, if they meet the requirements, and the requirements not just of age, but of mental capacity." Several US states have a form of physician-assisted suicide, as do countries including Japan, Belgium and Switzerland. Born in London in 1914, just months before the outbreak of World War I, Goodall and his family moved to Australia when he was a child. He went on to hold academic positions across the world, including in the UK, the US and Australia.