Up to 10,000 doctors working in Victoria's public hospital system are expected to take part in a statewide four-hour walkout on Thursday afternoon, as negotiations over pay and working conditions continue.

The planned industrial action will be the third doctors' stoppage in two months, but unlike previous walkouts affecting selected Melbourne and regional health services, Thursday's action is expected to involve doctors across the state.

The Australian Medical Association and the Australian Salaried Medical Officers Federation have raised concerns about doctors' working conditions, including long shifts and the number of consecutive night shifts being rostered.

According to the unions, doctors are seeking changes that would place limits on the length of individual shifts and consecutive night duties. They are also seeking a 28 per cent pay increase over four years.

The AMA said negotiations with the Victorian Government had continued for about 14 months without a pay offer being put forward. AMA Victorian president Simon Judkins said doctors remained frustrated by the lack of progress.

Union representatives have also raised concerns about fatigue. They say some doctors are being rostered for very long working weeks, with emergency situations sometimes extending working hours further.

The unions say the proposed industrial action is intended to draw attention to the working conditions of doctors across Victoria's public hospitals.

Emergency departments and intensive care units are expected to remain operational during the walkout. The unions have said staffing levels will remain above Saturday levels and that arrangements have been made to maintain patient safety.

However, the AMA has warned that some elective surgeries and other non-urgent hospital services could be disrupted by the industrial action.

The Victorian Government has said it is continuing to work with doctors and health workers. Government frontbencher Tim Richardson said the government wanted to ensure doctors received a suitable outcome through the negotiations.

The dispute has also attracted criticism from the Victorian opposition. Shadow Health Minister Georgie Crozier said the absence of a pay offer from the government was unacceptable.

The industrial dispute comes at a time when public hospitals across Australia are facing continuing pressure around staffing, workloads and demand for healthcare services.

Doctors' unions argue that changes to working conditions are necessary to address fatigue and improve the environment in which medical staff provide care. The government and hospital authorities will need to manage the impact of Thursday's action while negotiations continue.

For patients, the main expected impact is on planned or elective services rather than emergency care. Hospitals will provide further information to affected patients if appointments or procedures need to be changed.

The statewide walkout is scheduled for Thursday afternoon, with negotiations between doctors' representatives and the Victorian Government continuing.