JABBING a finger to make his point, Arthur Scargill is in full flow as he exhorts and encourages his followers in their struggle against their traditional class enemies. Only the angry orange hair signals that this is an image from the glory days of the past.

The huge painting dominates one wall of the president's vast office inside the imposing NUM headquarters in the centre of Barnsley, more akin to a castle than the home of one of the great class warriors.

It's a long time since the path to King Arthur's court was well-worn, as trade unionists and politicians came to pay homage. The orange hair is now grey and receding, a process it always seemed to be threatening when he was at the height of his fame and never off the television.

But, even at 63 and just two years off retirement, his appetite for the battle has not diminished. He led the fight against scrapping Clause Four of Labour's constitution, which committed the party to public ownership. Now, he is fighting one of the architects of New Labour, standing against Peter Mandelson in Hartlepool.

His decision to oppose the former Northern Ireland Secretary fulfils a pledge he made after debating the Clause Four issue with the Hartlepool MP, a debate he says he won, even though the eventual vote was lost.

"I told Peter Mandelson in March 1995 that I would challenge him in every way that I could, because I knew that his policies for the Labour Party were disastrous and would lead to massive unemployment and cutbacks in vital services. The following year I spoke in Hartlepool at the May Day rally and I repeated my pledge that I would campaign against him," he says.

Despite this promise, when the NUM president first stood for his Socialist Labour Party it was not in Hartlepool but in Newport East, when he opposed Alan Howarth, a much-heralded Labour recruit from the Tories.

Now, when New Labour has had a chance to put its policies into practice, he feels it is time to fulfil his commitment and prove who was right and who was wrong at that 1995 debate.

But, while it was the Clause Four issue which prompted his departure from the Labour Party, it was clearly a decision which he's been mulling over for some time. Characteristically, it is one he has never doubted. And, also characteristically, he is sure that those who felt the same way but decided to remain within the party, were mistaken.

'The people who have done that are very misguided, and a lot of them have been good friends of mine for years. If it was just a policy change, you have an opportunity to change it back, but what took place was fundamental because it changed the basic constitution of the party. It removed any commitment it had to socialism and common or public ownership, and, instead, is now firmly committed to the free market and, by extension, committed to capitalism.

"It was the easiest decision of my life, and the only regret I have is that I didn't do it years ago. When I look back at the constant attempts by the Labour Party to run this society more efficiently than the Tories, I'm appalled that I allowed myself to remain in that party."

Founding his own party means he can ensure he agrees with its principles, but he bristles at suggestions it is a one-man band. As well as the more than 6,000 members, including 2,500 individual members, and the leading trade unionists who have joined him, he can also point to the 116 candidates they are fielding in the election, the highest number by any left-wing party in Britain, he says.

The Socialist Labour Party's manifesto cover is unashamed red, and its policies are a reminder of what the Labour Party used to believe. Defence spending will be cut to provide an extra £15bn-a-year for the NHS, schools and colleges will get £5bn-a-year from the profits of industries privatised since 1979, and the £6bn cost of restoring the link between pensions and wages will be met out of the £10bn saved from withdrawing from the EU.

He takes as a compliment the suggestion that his views have changed little since the days he was the most renowned trade unionist in the country, presiding over 250,000 miners. During the 1984-5 strike, which he still insists was not a defeat, he became the most demonised, portrayed as the enemy within by his arch-enemy, Margaret Thatcher.

His union may have shrunk to less than a tenth of the size of its glory days, but he makes guest appearances in the newspapers every time they want to scare their readers. Ask him about his image and he trots out a familiar line, although it appears to hide a wistful resignation. "There are times when I don't even like myself," he says. "In a sense, I understand it. It can be unpleasant, obviously, but, you know, it is better to have coverage and to have the ability to appear on television or the radio or in newspapers. At least you can put your views across, even though you may get attacked for it."

This, he says, is better than the alternative, of being ignored, which is what he says happened to him for about eight years before this year. He tells of how the invitations to appear on radio and television stopped coming, how the only newspaper to report the 44 per cent pay award he won for his members in 1999 was the NUM's own, and how one BBC radio producer's repeated attempts to have him on a programme were vetoed by management. He notes that the end of his media exile coincided with Peter Mandelson's departure from the Cabinet earlier this year.

But, while his disillusionment with New Labour is complete - the only positive thing he can find to say about the Government is that it has called the election - he is not pessimistic. Anti-capitalist demonstrations in Seattle, Nice and London have given him renewed hope. "It is a sign of the deep-seated frustration, particularly among young people, who have simply lost faith in any politicians, and who see the only way out of this oppressive system is by taking direct action.

"I can appreciate their anger and their frustration, when they see people thrown out of work, they see people dying for the want of medical care, children unable to receive a decent education and ten million people in Britain today on or below the poverty line."

Anger and frustration is what Arthur Scargill does, and, at one time they were all the rage. With his socialist fervour and eagerness to engage in class war, he seems a relic from the past. But, at least, he does believe in something, and some day that may be fashionable again.