The health service is spending almost £250 million on locum doctors and nurses because staffing is "so stretched", Tory leader Ruth Davidson has said.

The Conservative MSP blasted the "rocketing" bill for agency staff, which she said had risen by £41 million on the previous year.

She said: "That's all because our hospitals don't have the staff needed to cover the rotas."

The Conservative Party contacted health boards across the country to find out how much they are spending on locum cover for medical and nursing staff.

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The Tory leader pressed Nicola Sturgeon on the issue at First Minister's Questions in the Scottish Parliament, telling her: "We see an NHS which has become so stretched that we are shelling out a quarter of a billion pounds a year on costly locum cover.

"The First Minister is on the slide because instead of rolling up her sleeves she is tearing up her promise not to hold a second referendum."

Ms Sturgeon insisted there has been a reduction of over 60% in agency staff working in the NHS since the SNP came to power in 2007.

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She added: "The reason Ruth Davidson wants to talk about independence is as a smokescreen for the almighty mess her party has created over the European Union."

With junior doctors in England taking industrial action, the SNP leader added: "Patients would probably prefer this government to continue to build on the success of our health service than have the Tory government in London, who of course have managed to force junior doctors out on strike."