THE NHS in Scotland is facing a record shortage of more than 3,400 registered nurses amid a threat of a walkout over pay.

Analysis by the Royal College of Nursing Scotland found that the shortfall between the number required to run the health service - known as the nursing establishment - and the number of registered nurses actually in post has soared from 1,613 in June 2015, to 3,438 by June this year.

The figures - published by NHS Education for Scotland - are based on counting nursing staff by 'whole-time equivalent' to take account of part-time working, and come despite the number of nurses by headcount in the NHS being at an all-time high.

RCN Scotland said it was particularly worried that the number of registered nurses by WTE fell by more than 400 between March and June this year alone.

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Its members are currently considering potential industrial action in a row over improved pay, which the union says is necessary help address staff shortages.

The indicative ballot will close on November 8.

RCN Scotland lodged a formal trade dispute with the Scottish Government for the first time ever in June after its members voted in May against a single-year pay deal, which was then imposed regardless.

The arrangement handed those on pay bands one to four a flat uplift of £1,009 and those on bands five to seven a 4% pay increase, tapering to 2% or an extra £800 a year for senior grade nurses.

However, RCN Scotland said this fell "far short" of the 12.5 per cent uplift it is seeking for all pay bands.

Colin Poolman, interim director of RCN Scotland, said: “Much more needs to be done to encourage our experienced nursing staff to stay and to ensure there is a robust plan to increase the future workforce.

"Implementing fair pay is part of the solution which is why RCN members strongly rejected the pay award made by the Scottish Government earlier this year."

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An indicative ballot for industrial action over pay has also gone out today to RCN members in England and Wales.

Scottish Labour health spokeswoman Jackie Baillie said: “Our NHS is teetering on the brink of the worst winter in memory and the SNP government has entirely failed to address the growing shortage of nurses in the NHS.”

Scottish Conservative Shadow Health Secretary Dr Sandesh Gulhane described the shortfall as "shocking".

He added: “It’s little wonder that waiting times are at record levels when our health service is short of more than 3,400 nurses."

A Scottish Government spokeswoman said there has been an 11% increase in qualified nurses and midwives over the past nine years and "a steady rise" in places on pre-registration nursing and midwifery undergraduate training programmes. 

She added that the £300 million winter plan includes £11m for new national and international recruitment campaigns and to establish a national Centre for Workforce Supply. 

She said: “The establishment requirement has also increased, not least due to efforts to expand the NHS workforce further.

"Part of our winter package for the NHS includes efforts for Health Boards to attract at least 200 registered nurses from outwith Scotland.

"We are also recruiting 1,000 additional healthcare support staff to support patients in hospitals and in community health teams.”