The letter from the Our Duty of Care campaign group is signed by over 3,400 doctors and nurses, from every specialism, including 49 professors of medicine, nearly 100 palliative care doctors and nearly 700 GPs.
Dr Gillian Wright, who co-authored the letter, commented: ‘Our letter to the Prime Minister highlights our grave concerns around changing the law as assisted suicide affects us all, our patients, their families and medical staff.
‘Healthcare professionals from across all medical specialties, GP, palliative, hospital, community and hospice echo that we will not help patients to take their own lives, because of the pressure that disabled and dying people so often feel under, whether real or perceived.'
The signatories warn the right to die could ‘become a duty to die, with the ‘poorest people in society more likely to be euthanised than their richer neighbours'.
‘We underline the fundamental value and worth of individual lives and call for better palliative, social and psychological care for those who are dying, desperate or distressed,' Dr Wright added.
MPs are to be given a free vote on the legislation that is expected to appear before Parliament later this year.
A Government spokesperson said: ‘We understand this is an incredibly emotive issue, and there are strongly held views on all sides of the debate.
‘As a matter of conscience, it is right that any changes to the law around assisted dying are decided by Parliament.'