France's President Emmanuel Macron said a bill on assisted dying would go before parliament in May, speaking in an interview published by French media on Sunday.
Only adults with full control of their judgement, suffering an incurable and life-threatening illness in the short to medium term and whose pain cannot be relieved will be able to "ask to be helped to die", Macron told newspapers La Croix and Liberation.
Minors and patients suffering psychiatric or neurodegenerative conditions such as AlZheimer's will not be eligible.
If medical professionals give their consent, a lethal substance will be prescribed for the patient, who can administer it themselves or with the help of a third party if they cannot physically do so.
The third party can be a volunteer, the doctor or the nurse treating the patient, according to the text, while the substance can be administered at the patient's home, in care homes for the elderly or care centres.
Medical experts will have 15 days to respond to the request for help to die and an approval will be valid for three months, during which time the patient can retract, Macron said.
Macron said that if medical professionals rejected the request, the patient could consult another medical team or appeal.
He added that he wanted to avoid the terms assisted suicide or euthanasia because the patient's consent is essential, with a role for medical opinion and "precise criteria".
Until now French patients in pain wishing to end their lives have had to travel abroad, including to neighbouring Belgium.
A 2005 law has legalised passive euthanasia, such as withholding artificial life support, as a "right to die".
A 2016 law allows doctors to couple this with "deep and continuous sedation" for terminally ill patients in pain.
But active euthanasia, whereby doctors administer lethal doses of drugs to patients suffering from an incurable condition, is illegal.
Assisted suicide -- whereby patients can receive help to voluntarily take their own life -- is also banned.