Amazon's Alexa is set to answer people's health queries by searching the official NHS website.

Until now, people asking Alexa a health question would be given an answer based on a variety of popular responses.

But a new partnership with the NHS means Alexa will now give answers based on information from the health service website, which has been verified by health professionals.

The plan is to help patients, especially the elderly, blind and those who are unable to access the internet in other ways, take more control of their healthcare and help reduce the burden on the NHS.

The Royal College of GPs welcomed the move but warned that independent research must be carried out to ensure the advice given is safe.

Privacy campaigners Big Brother Watch said the move was a "data protection disaster waiting to happen".

Health Secretary Matt Hancock said: "We want to empower every patient to take better control of their healthcare and technology like this is a great example of how people can access reliable, world-leading NHS advice from the comfort of their home, reducing the pressure on our hardworking GPs and pharmacists."

However, The Times reported that Mr Hancock had dismissed the idea of using voice-assisted technology at a Times/Red Box event last May when he was culture secretary.

He said that he did not own an Alexa-enabled device "and I wouldn't want one", adding: "I don't want one because I think there is an essential humanity that we have got to preserve.

"We haven't as a society and as individuals yet at all come to terms with how we use this technology for the better."

Amazon's algorithm will use information from the NHS website to provide answers to questions such as: "Alexa, how do I treat a migraine?", "Alexa, what are the symptoms of flu?" and "Alexa, what are the symptoms of chickenpox?".

The new partnership has been spearheaded by NHSX, an NHS body set up to bring digital technology to patients.

Professor Helen Stokes-Lampard, chairwoman of the Royal College of GPs, welcomed the move but urged caution, saying: "This idea is certainly interesting and it has the potential to help some patients work out what kind of care they need before considering whether to seek face-to-face medical help, especially for minor ailments that rarely need a GP appointment, such as coughs and colds that can be safely treated at home.

"However, it is vital that independent research is done to ensure that the advice given is safe, otherwise it could prevent people seeking proper medical help and create even more pressure on our overstretched GP service.

"While some patients might want to use symptom-checkers in this way, not everyone will be happy to do so and many people will not be able to afford the expense of this equipment, thus widening health inequalities and making access to care even harder for some of the most vulnerable people in our society.

"Patients who are frail often have more complex healthcare needs so it is important that they do not rely on this as their sole source of health advice."

Silkie Carlo, director of Big Brother Watch, said: "Encouraging the public to give their private health details to one of the most aggressive corporate data guzzlers is astonishingly misguided.

"Amazon's Alexa records what people say, stores recordings in data centres we know nothing about, and exploits our data for profit.

"This scheme will likely result in people being profiled and targeted by data brokers based on their deeply personal health concerns.

"These home surveillance devices are controversial and not widely used. Any public money spent on this awful plan rather than frontline services would be a breathtaking waste.

"Healthcare is made inaccessible when trust and privacy is stripped away, and that's what this terrible plan would do. It's a data protection disaster waiting to happen."

Matthew Gould, chief executive of NHSX, said: "By working closely with Amazon and other tech companies, big and small, we can ensure that the millions of users looking for health information every day can get simple, validated advice at the touch of a button or voice command."

Tech experts predict that by 2020, half of all searches for information will be via voice-assisted technology.