The "Affirm Dignity-End Euthanasia" campaign has highlighted Belgium and the Netherlands as countries of particular concern as the annual numbers of euthanasia there continue to increase.
"The slippery slope is on full public display in Belgium, and we can clearly see the tragic consequences," said Paul Coleman, Executive Director of ADF International.
"According to the most recent government report, more than six people per day are killed in this way, and that may yet be the tip of the iceberg. The figures expose the truth that, once these laws are passed, the impact of euthanasia cannot be controlled.
"Belgium has set itself on a trajectory that implicitly tells its most vulnerable, including the elderly, that their lives are not worth living. This is not an example that other countries should follow."
In Belgium, these laws were amended in 2014 to also include children.
The campaign aims to inform about the reality of euthanasia through personal stories and testimonies, ongoing legal cases, and research into the impact of euthanasia.
Robert Clarke, director of European Advocacy for ADF International said: "The legalisation of euthanasia implicitly tells the most vulnerable that they are a burden. With this campaign, we want to send the opposite message."
The campaign, which has been launched a day before World Hospice and Palliative Care Day, encourages people to show their support by signing the Affirm Dignity Charter online.
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