By Ian Dunt

Gordon Brown has gone about as far as politically possible to intervene in the debate over American adverts casting the NHS in a bad light, by tweeting his support for the institution.

Anger across Britain grew by the hour yesterday as details spread of the US adverts showing across the Atlantic.

The ads, paid for by a right-wing group, made several damaging assertions about the NHS in an effort to prevent President Barack Obama's healthcare reforms.

Comment: Why I'll never understand Americans

The ads were followed by damaging debate in the US, in which the NHS was branded "evil" and "Orwellian".

But British anger over the misleading ads spread throughout the internet, focusing, predictably, on Twitter.

A campaign entitled #welovethenhs was set up, and quickly received so much support the site crashed.

Gordon and Sarah Brown, and health secretary Andy Burnham, eventually sent in their own messages of support.

The prime minister wrote: "NHS often makes the difference between pain and comfort, despair and hope, life and death. Thanks for always being there."

Mr Burnham wrote: "Over the moon about strong support for the NHS - an institution I will defend to my dying day, second only to Everton FC."

At one point yesterday, the hash tag was attracting 750 new tweets every five seconds.

Meanwhile, Tory MEP Daniel Hannan has come in for criticism after he went on American Television to say the NHS was a "60-year mistake".

"I wouldn't wish it on anybody," he continued.

Shadow health secretary Andrew Lansley rebuked Mr Hannan: "There are millions of people who are grateful for the care they have received from the NHS.

"It does them and the NHS a disservice for Daniel Hannan to give Americans such a negative and partial view. That we can access healthcare free at point of use, based on need, is something others envy."

Former deputy prime minister John Prescott hit back at the comments as proof of the Conservative party not pursuing a progressive agenda.