Watch: Moment nurses walk out on strike
Health staff in Northern Ireland are taking to the picket lines on Monday as part of 24-hour strike action, in a row over pay and conditions.
NHS workers from Unison, GMB and NIPSA are all walking out, three years after the last nurses strike.
Royal College of Nursing staff will then stage the first of a series of strikes on Thursday, followed by more the following Tuesday.
The union is demanding a wage rise of 5% above inflation following a ballot among more than 300,000 RCN members. Patients could face disruption to operations and appointments, though nurses are to continue providing emergency care.
Last week, Stormont's Department of Health announced that healthcare workers would receive a pay rise recommended by independent salary review bodies.
Unions said the increase was not enough and insisted the strike action would continue.
The delayed pay rise move came after civil servants secured the legislative authority to make decisions on pay amid Stormont's political impasse.
Decisions on other public sector employees, such as teachers, civil servants and police, are awaited.
The majority of health workers are to receive at least an additional £1,400 in pay while doctors and dentists will be given a 4.5% rise.
The increases will come into effect before the end of the financial year and be backdated to April 1 this year.
The separate independent recommendations were made by the NHS Pay Review Body and Review Body on Doctors' and Dentists' Remuneration.
The announcement was always unlikely to have affected the industrial action planned by health workers, as NHS colleagues in Great Britain have voted to strike having already received the 2022/23 rises.
The lack of a devolved executive at Stormont had prevented the awards being made in Northern Ireland before the UK Government intervened last month to pass a budget for Stormont and hand civil servants extra powers.
Anne Speed, Unison's Northern Ireland head of bargaining and representation, said she was proud of members for taking a stand on Monday.
"In freezing temperatures and from early morning Unison members across the health service are stepping out and standing up for themselves in their just campaign for a decent pay rise," she said.
"The decision by Secretary of State Chris Heaton-Harris to include an extension of budgetary powers to allow the Department of Health to apply a below-inflation pay award will not provide health staff protection against inflation.
Health staff remain adamant that a better deal should be delivered.
"These workers deserve support.
"They are the ones who every day cope with all the difficulties of a depleted workforce.
"They are the ones who struggle to maintain patient safety in extremely challenging circumstances.
"When they took action three years ago our frontline and nursing members demanded that steps be taken to tackle these issues.
"Notwithstanding the interruption of the Covid pandemic, we are back at that same spot.
"How does a workforce cope when political leadership is absent?
"We are very proud of our members for their courage and determination to bring to account those who should do better.
"We also commend the action of those members of Nipsa and the GMB who will be on strike today."
The Northern Ireland Ambulance Service (NIAS) have also forecast significant disruption to their services.
The NIAS stated: "Regrettably we will not be able to provide our full level of non-emergency transport to hospital appointments and will be prioritising available resources for cancer and renal patients and for emergency paediatric transfers.
"Resources will be prioritised towards Category 1 and Category 2 calls as they are the most clinically urgent.
"NIAS will seek to ensure that the less urgent needs of Category 3 and Category 4 patients are responded to in as timely a manner as possible"
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