Non-urgent outpatient appointments and operations at hospitals around Wales will be suspended as the government works to delay the spread of coronavirus.
Health Minister Vaughan Gething said he has taken "decisive action" to "provide care and support to the most vulnerable people in our communities, whilst also making sure organisations and professionals are supported."
During a press conference in Cardiff, the Health Minister said a "worst case scenario" would see around 25,000 deaths in Wales.
An average flu season would see 8-10,000, he said.
He said a larger number of people requiring high levels of care is "highly likely over the coming weeks."
It comes after Public Health Wales confirmed a further 13 cases of Covid-19 on Friday, taking the total number of cases to 38.
Mr Gething added, "In every decision I make, the health of the people of Wales is my overriding priority.
"There are many difficult weeks ahead of us. We need the public to play their part in following the advice that our NHS and Welsh Government give."
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The new measures announced by the Welsh government include relaxing targets across the NHS and "fast track" older people into care homes when they are discharged from hospital.
Suspend non-urgent outpatient appointments and ensure urgent appoints are prioritised
Suspend non-urgent surgical admissions and procedures
Prioritise use of Non-Emergency Patient Transport Service to focus on hospital discharge and ambulance emergency response
Discharge of vulnerable patients from acute and community hospitals
Relax targets and monitoring arrangements across the health and care system
Minimise regulation requirements for health and care settings
Fast track placements to care homes by suspending the current protocol which gives the right to a choice of home
Permission to cancel internal and professional events, including study leave, to free up staff for preparations.
Relaxation of contract and monitoring arrangements for GPs and primary care practitioners
Suspend NHS emergency service and health volunteer support to mass gatherings and events
“Health boards and health care providers will begin to contact anyone affected by these decisions over the coming days as these actions are phased in", Mr Gething said.
"Access to cancer and other essential treatments such as renal dialysis for example will of course be maintained.
“Our NHS 111 online and telephone service is available and has been protecting our vital primary care and emergency department services from undue demand."
When asked about the last-minute postponement of Wales' final Six Nations match in Cardiff against Scotland, Mr Gething said the medical advice on large gatherings has not changed but added, "given other events in the sporting community, I understand why they [the WRU] took the decision to call it off".
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