More than 600 French hospital doctors have threatened to resign if the government does not increase health funding, as striking medics prepare to take to the streets this week across the country.

The doctors warn that budget cuts, bed closures and staff shortages are bringing France’s health system to the brink of collapse and putting patients’ lives at risk.

“Public hospitals in France are dying,” wrote 660 medics from hospitals all over France in an unprecedented open letter, saying funding cuts were threatening patient safety in what was once seen as one of the best healthcare systems in the world.

Doctors are calling for urgent government talks after nine months of hospital strikes, which began in March in emergency rooms and have since spread across departments from paediatrics to psychiatry, with junior doctors joining this month and no end in sight.

On Tuesday, medics will march across France carrying banners saying: “Public hospitals: a life-threatening emergency”. The long-running healthcare strikes are proving a major headache to the centrist president, Emmanuel Macron, with rail workers now adding to his troubles by carrying out nationwide stoppages against pension changes.

Macron’s pledge last month of more hospital funding and staff bonuses was rejected by doctors’ groups as not enough.

In 2000, the World Health Organization ranked France’s health system the best of 191 countries. But a study by the Institute for Health Metrics and Evaluation, published in the Lancet medical journal in 2017, placed it in 15th place for quality of care.

“For years we’ve watched from afar with a lot of empathy as UK healthcare staff struggle under NHS funding cuts,” said Cathy Le Gac, a Sud union representative, who worked for 19 years as a trauma nurse, dealing with serious car crash accidents north of Paris. “And yet, now in France, funding cuts mean we’re seeing similar problems to our NHS colleagues.”

For many years, governments on the right and left have reduced funding. Public hospitals in France have been forced to cut €9bn in spending since 2005, leading to the scrapping of hundreds of beds and dozens of operating theatres while stagnant salaries fuelled a flight to the private sector. Emergency room staff complain of elderly patients being left for hours on trolleys in corridors, not enough equipment, increased waiting times for operations and even deaths.

At one Paris hospital this year, medics blamed staff shortages for the death of a 55-year-old woman on a trolley in a corridor, while the hospital management maintained staffing numbers were fine. Doctors also warn of staff suicides. More than 400 medical staff marched in Flers, Normandy, in September, after a senior member of the psychiatry department took his life with colleagues blaming poor working conditions.

Adeline, 36, a nurse in a hospital in the south of Paris, said despite looking after ageing patients with multiple issues, staff shortages and cuts meant there was not enough time for proper equipment or washing patients. “We used to have big towels, now there are small towels that don’t dry; our machines for reading blood pressure are old and there aren’t enough of them,” she said. “Even crucial cream for our patients’ private areas, to prevent sores – we used to have large tubs and are now given small tubes. Some services have no more bin-bags. The idea seems to be rot the health system from the inside and then say it doesn’t work.”

Like many nurses – whose pay is lower than in countries such as Germany, and who often live on the periphery of towns, struggling to make ends meet – Adeline took part in the gilets jaunes anti-government protests earlier this year. Unions said many nurses were quitting the profession due to burn-out.

Fanny Rigaud, a healthcare assistant at a major Paris hospital, said: “I work with young people being treated for leukemia. They’re scared, we need to reassure them, that takes time but we’re constantly under time pressure.”

In an effort to calm the tension, Macron has shifted his approach to the hospital crisis. For months he had maintained that hospitals and emergency rooms were struggling principally due to the way healthcare was organised, citing the lack of general doctors who should be treating patients in towns and rural areas. But last month he also acknowledged the need for more funding. “We must invest more than we first envisaged because the situation is worst than we had thought,” he said.

But the government’s promise to give an extra €1.5bn over three years, including staff bonuses, was brushed aside as too little by medics, who vowed to continue the protests. The government also promised to absorb €10bn of debt from public hospitals.

Some 87% of French people support the hospital strikes, according to ViaVoice pollsters, with the public deeply concerned about protecting universal healthcare as a pillar of the social system. Over 90% of people trust healthcare staff to do their best with limited resources. But crucially, 73% are pessimistic about the future for healthcare.

Stewart Chau, a sociologist and consultant for Viavoice, said pressure was acute on Macron because “while France is currently living a period of social crisis and tension, the health system is seen as a key right and common good that must be protected – a plank of the French social security system.”

Pierre-André Juven, a sociologist and research fellow on health systems at the French National Centre for Scientific Research, said: “Medical staff feel there is so much pressure and time-constraint that they cannot do their jobs right, even though they want to.” He said France valued its universalist system of protecting everyone “but inequalities in access to healthcare are growing in France, alongside great difficulties in hospitals, that’s why this protest movement is going on for so long.”

Olivier Youinou, who had been working for almost 30 years as a highly specialised anesthetics nurse in a hospital in Créteil outside Paris, said: “I had better working conditions when I started than I do today.”