By Nick Triggle
BBC News health reporter in Bournemouth
The government is skating on "thin ice" and risks losing the support of nurses, the profession's leader says.
Dr Malone warns nurses' goodwill is under threat
Royal College of Nursing general secretary Dr Beverly Malone told ministers to start treating nurses like "valued professionals".
Speaking at the RCN's annual conference, she said nurses support reforms that benefit patients.
But she added they are prepared to oppose change as well if they perceive the future of the NHS to be threatened.
More than 2,000 nurses are expected at the conference in Bournemouth where NHS deficits, privatisation and providing care in the community will be discussed.
Her speech comes after Health Secretary Patricia Hewitt was condemned for saying the NHS had enjoyed its "best year ever".
Ms Hewitt said there had been no winter bed crisis and waiting times were at their lowest ever level.
Ms Malone said that the government should remember that NHS services, patient care and successful reform relies "on the goodwill of nurses".
She said: "If they want proof they should take a long hard look at the unpaid overtime worked by nurses - an average of one day extra every week of the year.
"Undermine and lose that goodwill and our healthcare system will be plunged into crisis.
"So government, listen up, you need to stop treating us like overheads to be cut and start treating us like valued professionals.
"Because if you don't, the goodwill of nurses is going to melt away like ice in the Spring.
"And believe me, right now, the ice that ministers are skating on doesn't come any thinner and it is melting fast."
Ms Malone told nurses it has been a year of "tough and testing times".
She attacked the government over its pension provision and 2.5% pay deal for nurses, saying she shares "the hurt, the upset, and frankly the anger that many nurses feel towards it."
Speaking at a press conference after her speech, Dr Malone said nurses feared they would be pushed into a situation where providing care would resemble working in a factory.
If the situation with job cuts and deficits continued, nurses would consider taking action.
She said nurses worked the equivalent of one day of unpaid overtime a week and could withdraw from doing that in what would effectively amount to a work to rule.
"We are talking a long way down the line. But we may consider not working those hours, but such action is always a last resort because nurses are always going to be looking at how to make sure patients are safe."
RCN President Sylvia Denton also urged the government and others to stop patronising nurses by calling them "angels".
She said nurses had shared values, but added: "What these values don't do is make us 'angels'.
"I'm sick of the angel tag because for years it has allowed governments and employers to pat nurses on the head, say how wonderful we are, argue that nursing is a vocation rather than a job, and then use that as an excuse to leave us overworked, overstretched and underpaid."
But Chief Nursing Officer Christine Beasley defended the government''s record, saying money has been invested.
"We have 80,000 more nurses than in 1997, with starting pay rising by 55% in the same period.
"In the minority of hospitals currently in deficit the threat of compulsory redundancy will be contained to as few people as possible and in many cases changes will be achieved through cutting down on agency staff."