A Greater Manchester NHS boss has warned members of the public to stay away from A&E departments unless it is a "life-threatening emergency".
The Greater Manchester Integrated Care Board, which oversees the NHS in Greater Manchester, said demand for NHS services following Christmas were unprecedented.
Professor Jane Eddleston, Greater Manchester medical executive lead for acute care, said: “The first day back after the Christmas break is always busy for NHS services but today has been beyond anything we have experienced before.
“We are making an urgent plea to the public in Greater Manchester to only call 999 or attend accident and emergency departments if their condition is a life-threatening emergency."
She added: “Unprecedented levels of attendance at A&E, staff sickness and increased prevalence of flu and covid have led to very long waits in emergency departments and for ambulances.
"We urge the public to use alternative services to make use of NHS 111 online and phone services (111 online is for people aged five and over).
“Accessing NHS 111 online, contacting your GP, or attending your local pharmacist will mean you get treatment much sooner.
"GP practices and pharmacies are open as normal between Christmas and new year.
“As we head into the new year, we also urge anyone experiencing flu or Covid-like symptoms to stay at home, so that you do not pass on your infection on to others.
“Both can be serious illnesses, so please take the necessary precautions to protect your loved ones, particularly those who are vulnerable, including getting your vaccines if you are eligible.”
NHS England figures show that half of patients attending major A&E at the Northern Care Alliance NHS Foundation Trust, which runs Fairfield General Hospital, Royal Oldham Hospital and Salford Royal, had waited longer than four hours to be dealt with last month.
Earlier this month it came to light that 30,000 operations had been cancelled in England due to staff shortages last year.
Additionally, the Royal College of Nursing said that, unless negotiations were opened, its members would walk out on Wednesday, January 18, and Thursday, January 19 as part of a pay dispute with the Government.
Prime Minister Rishi Sunak insisted that refusing to negotiate on public sector pay was the "right thing".
Additionally, ambulance workers in Unison are set to stage two new strikes on Wednesday, January 11 and Monday, January 23, following strike action earlier this month.
The Department for Health and Social Care has been contacted for comment.
Comments: Our rules
We want our comments to be a lively and valuable part of our community - a place where readers can debate and engage with the most important local issues. The ability to comment on our stories is a privilege, not a right, however, and that privilege may be withdrawn if it is abused or misused.
Please report any comments that break our rules.
Read the rules here