About two-thirds of all anaesthetists in Poland have threatened to resign unless the government agrees to pay rises.
Union leaders said some eighteen-hundred of the country's two-thousand-seven-hundred anaesthetists had written to the Ministry of Health, threatening to quit after New Year's Day unless the government opens pay talks.
A government reform of health care in Poland takes effect on January-the-first.
The ministry has accused the anaesthetists of blackmail.
Many anaesthetists, like other Polish workers, take second jobs to supplement their salaries.
From the newsroom of the BBC World Service