The good will of nurses in England is being abused by politicians who have failed to get to grips with a desperate shortage of staff, nurse leaders say.
Royal College of Nursing general secretary Dame Donna Kinnair will call for safe staffing levels to be enshrined in law in a speech on Monday.
There are currently nearly 40,000 nurse vacancies - one in nine posts.
However, the government says it is committed to increasing the number of nurses in training.
But Dame Donna, in an address to the RCN's annual conference in Liverpool, will say this is not enough.
A report earlier this year by three leading think tanks if action was not taken.
Dame Donna will say the situation has been made worse by the removal of a student bursary for trainees and the introduction of tuition fees in 2016.
She will also say the good will of nurses is being abused - and that ministers need to consider the financial and human cost of leaving jobs unfilled.
'Safe staffing levels needed'
She will demand tougher rules on safe staffing be introducing, criticising the "vague metric" currently used which does not distinguish between care provided by registered nurses or healthcare assistants.
Dame Donna will point to the new staffing law in Scotland, which cleared its final parliamentary hurdle earlier this month, as evidence of how legislation can be introduced.
Scotland is now the second country in the UK to set staffing accountability in law after Wales became the first in Europe to legislate in 2016.
She will say: "We will not stop until people are held to account for the desperate shortages each and every one of us has witnessed. Politicians must stop short-changing the public.
"They must stop the rot and put an end to the workforce crisis in nursing.
"Rather than only looking at the cost of educating and employing nurses, the government must think about the true cost - financial and human - of not doing it.
'Employers, decision-makers and ministers with the power to change things should not let individual nurses take the blame for systemic failings.
"The goodwill of nursing staff is being abused and politicians must know it is running out. I will not stand by while this profession is denigrated."
The Department of Health and Social Care has already announced plans to increase training places by 25% - and the NHS in England is now working on a long-term plan for the workforce.
A spokeswoman praised the "commitment" of nurses and said the government would "secure" the staff the service needed.