Nurses for England, Wales and Northern Ireland don start nationwide strike, dis na di largest strike for NHS history.

Staff go continue to provide "life-preserving" and some urgent care but routine surgery and oda planned treatment fit dey affected.

Di Royal College of Nursing say staff bin no get choice afta ministers refuse to reopen pay toks.

UK goment say di RCN19% pay rise demand no dey affordable.

RCN general secretary Pat Cullen don call on goment to "do right thing" and resolve di matter before di year end.

Madam Cullen tell BBC Breakfast say di strike na "tragic day for nursing".

"We need to stand up for our health service, we need to find a way to address those ova seven million pipo wey dey sit on waiting lists, how we go take do am? To make sure say we get nurses to look afta our patients, no be wit di 50,000 vacant posts, wey dey increase day by day," she tok..

Di action go involve nurses for around a quarter of hospitals and community teams for England, all health boards in Northern Ireland and all but one in Wales. But nurses no dey strike for Scotland.

Under trade union laws, di RCN make sure say life-preserving care go continue during di 12-hour strike.

Chemotherapy and kidney dialysis suppose run as normal, along wit intensive and critical care, children accident and emergency and hospital neonatal units, wey dey look afta newborn babies go work.

Aside that, e go dey up to NHS boards and trusts to negotiate services for local level, discussions dey likely to come down to di circumstances of some individual patients.

Di biggest impact go be pre-booked treatment like hernia repair, hip replacements or outpatient clinics.

NHS say e dey "important"  say pipo continue to come forward for emergency care during di strike period and anyone wey dem no contact to reschedule an appointment, suppose go dia appointment as planned.

"Nurses don tire - we dey underpaid and undervalued," nurse anaesthetist and local RCN steward Lyndsay Thompson, from Northern Ireland, tok.

"Yes, dis na pay palava but na also about patient safety.

"Di fact say we no fit recruit enough nurses means patient safety dey at risk."

Madam Thompson, wey bin work as a registered nurse for 12 years, say her colleagues "absolutely bin no want to strike" but feel di need to take action "to protect di NHS" afta a period of below-inflation pay rise.

"We just feel say we no get anoda option, because di goment no dey listen to us," she tok.

Di RCN ballot more than 300,000 nurses across individual NHS trusts and boards rather than in a single, national vote.

E mean say some nurses no fit go on strike, because di turnout for local area dey too low.

For England, di first round of strikes go, go ahead for 51 of 219 hospitals, mental-health trusts and community services.

Strikes dey also take place for Northern Ireland health boards and all but one for Wales, di Aneurin Bevan.

Most GP services no go dey affected, as nurses wey dey work directly for practices no fit take part for di vote, but di strike go include district nurses wey dey work for pipo  homes or community settings.

Di second day of strike action go take place  December 20, unless dem solve di palava.

How patients go dey affected?

- Pipo wey dey seriously ill or injured, and wey dia life dey at risk, fit call 999 as usual, or call 111 for non-urgent care
- Oda services, like some cancer treatments, mental health services or urgent testing, go dey partially staffed
- More routine care dey likely to dey badly affected, including plan operations such as knee and hip replacements, community nursing services and health visiting
- Official advice na say anybody wey get appointment to turn up for di time wey dem give dem if dem no rearrange am
- GPs, community pharmacies and dentists no go dey affected

For England and Wales, most NHS staff don already receive a pay rise of roughly £1,400 dis year – wey dey worth about 4% on average for nurses.

Di political situation for Northern Ireland mean say delay bin dey to process di increase - but nurses go receive backdated payments before di end of di year.

Di RCN want a larger rise, of 5% above di RPI inflation rate, wey currently stand at 14%, e say dia members bin receive years of below-inflation pay increases.