Michael Sheen has savaged "bland" politicians for cutting the NHS as he urged crowds to fight to stop the health service from being systematically "undermined".
Speaking on Sunday in Tredegar, the birthplace of NHS founder Aneurin Bevan, the Newport-born Hollywood actor accused politicians of "sniffing around for markets to exploit, for weaknesses to expose".
"There are plenty out there who believe in grabbing as much as you can," he said, adding: "They won't say it of course, they're too smart for that."
"For decades there has been a systematic undermining of [the NHS's] core values, this is beyond party politics," he told assembled activists. "The Labour government arguably did as much damage as any Tory or coalition government, this is about who we want to be and what we believe is worth fighting for."
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In his St David's Day speech, Sheen, who has played former prime minister Tony Blair in a trilogy of films including The Queen and The Special Relationship, spoke of Nye Bevan's vision when he founded the NHS.
Michael Sheen as Tony Blair
"It was long term, it was far reaching. Visionary in its scope and revolutionary in its effect. He [Bevan] had cast-iron integrity and a raging passion," he said. "This was a man who had no fear in standing up for what he believed in, and he made no bones about how he felt. This is a man who publicly stated: 'No amount of cajolery, no attempt at ethical or social seduction can eradicate from my heart a deep, burning hatred for the Tory Party.'"
Sheen's appearance came in support of activists involved with the ‘People’s March for the NHS’, as one of a series of events planned all over the UK in protest at NHS privatisation.
Sheen at the protest
He asked those assembled: “What sort of society do we want to be? It is a choice. Do we want to be a society that is fractured, divided, disconnected, mistrustful of its own people – that sees people as commodities, instruments of profit? Or do we want to be a society where all are equal in value, and that value is not purely a monetary one?”
“We do not turn our backs on those facing hard times. We do not exploit their weaknesses - because ‘they’ are us. If not now, then at some point in the future."
Sheen's strident speech has already made waves online, with some Twitter users suggesting he should give up acting and go into politics.
Labour and the Tories have been in a war of words over which party has overseen a greater privatisation of NHS services. In an awkward interview last month, shadow health secretary Andy Burnham refused to specify how much private sector involvement he felt was right.
"The vast majority of outsourcing was done, 4.4%, in the last Labour government," BBC Newsnight presenter Kirsty Wark pointed out, with the help of a graph.
BBC Newsnight's private sector involvement graph
The Liberal Democrats have pledged to protect the NHS from cuts, while Ukip, which has faced many accusations of wanting to cut the health budget, insists it would not cut front-line services.
Speaking at the party's conference over the weekend, Mark Reckless MP told activists: "To go beyond our base we will show that Ukip is the party of the NHS," he said."I was born into the NHS. My father was a doctor and my mother was a nurse. Three times the NHS has been a lifeline for our party leader. Ukip is the party of the NHS."
A Department of Health spokesman said: "Official NHS accounts show that use of the private sector amounts to only six pence in every pound the NHS spends. Charities, social enterprises and other providers of healthcare play an important role in the NHS, as they have done for many years.”