SNP deputy leader Nicola Sturgeon repeated party pledges today that scrapping prescription charges will signal a return to the core values of the NHS as it approaches its 60th anniversary.

Speaking at the start of the SNP's annual conference, Ms Sturgeon said that the charges amounted to "a tax on ill health", and confirmed that the Scottish Government will scrap them within the next four years.

The health secretary told delegates in Aviemore: "I am announcing today and confirming today that prescription charges will be abolished completely for all, and will be abolished within the lifetime of this parliament.

"I think that's an amazing commitment for this Government to make."

Ms Sturgeon told how she had met Parkinson's disease sufferers at a conference last week who could not afford all their prescriptions.

"I think that's unacceptable," she said.

"And it's not a situation I as a health secretary am prepared to preside over."

With the 60th anniversary of the National Health Service next year she said: "I can't think of a better way to celebrate the 60th anniversary of the health service than by returning to its core founding principle of the health service being free."

In a wide-ranging speech, Ms Sturgeon also told delegates she was "increasingly sympathetic" towards an opt-out system for organ donation, where it would be assumed people were willing to donate vital organs after their death, unless they had specifically said otherwise.

A recent survey showed 74% of people in Britain were in favour of such a method.

Ms Sturgeon told how since becoming health secretary she had watched surgeons at Edinburgh Royal Infirmary carry out a live liver transplant.

She said: "It really brought home to me the vital importance of encouraging more people to sign up as organ donors so these surgeons and their colleagues right around the country can save even more lives.

"It is a hard fact that right now in Scotland at least one person dies every single day waiting for an organ transplant."

And she added: "I'm aware there is a growing tide of opinion, not just in Scotland but in many countries across Europe, that it might be time to change the law on organ donation, to move to an opt-out rather than an opt-in system of consent, where people are presumed to be willing to donate their organs unless they have expressed a contrary wish during their lifetime."

She also told delegates that she wanted GPs to become more flexible in their opening hours.

"It's true that for many patients accessing their GP between 8.30am and 6.30pm will be perfectly adequate.

"But for others who commute to work, being able to access a GP in the early evening or on a Saturday morning would be much more convenient and would make life a lot easier. And it's that flexibility of access that I want to see."

She said there would be discussions with doctors' leaders over how to achieve this.

But she said: "It will be a discussion about how, and not if, we make those changes, because I have got no doubt more flexible access is important and in the interests of patients."