A charity support worker fears people could die as a result of the way they are assessed for benefits.
The concerned staff member from Scottish Veteran Support claims a long-standing agreement with GPs to provide letters for housebound unemployed people has been altered.
The man, who asked to remain anonymous to protect his clients, said he would often approach a doctor for proof people are too sick to leave the house when ordered to attend benefit assessment centres.
The support worker said: “There are three assessment centres in Dundee and we have had people without arms or legs, or with serious mental health issues receive letters telling them to go down to be assessed.
“Some of them have been housebound for years and couldn’t go down if they tried. Until last week we got a letter from a GP to show how bad they are.
“One of my clients is suicidal but she received a letter telling her she had to be assessed.
“When I wrote to her GP service they said they have had a directive to say they can’t write letters anymore.
“We’re cutting off a lifeline to the most vulnerable people in society.
“People could die.”
The guidance was issued by Tayside Local Medical Committee, a group which represents GPs across Tayside.
A spokeswoman explained: “When patients are applying or appealing any form of benefits entitlement then the relevant government department may benefit from additional medical information.
“This information may be from their GP.
“Should this be the case then the relevant agency have established processes to seek this information directly from a patient’s GP.
“Allowing this process to apply for all patients ensures a consistency and equity of assessment for all applicants.
“It is therefore the advice of the Local Medical Committee, in line with others across Scotland, to advise practice not to provide letters on an ad-hoc basis to those patients requesting them as this risks inconsistency and opens the practice to accusations of discriminatory practice.”
A spokesman for the Health Assessment Advisory Service, which arranges and carries out the assessments on behalf of the Department for Work and Pensions, said their processes had not changed.