The Labour Party has defended itself against charges that it is has deserted its core supporters in the pursuit of power and government.

Speaking as the party prepared to celebrate its centenary on Sunday, Cabinet Office Minister Ian McCartney said Labour remained true to the members who had stuck with it through 18 years in opposition.

But in a separate BBC News Online webcast on Labour's centenary, veteran leftwinger Tony Benn said that New Labour was driving socialists from the party.

Mr Benn said: "Tony Blair said that New Labour is a new political party. He said, 'we were elected as New Labour and we will govern as New Labour'.

"One of the great tragedies was the setting up of a new party called New Labour.

"You can't wish away centuries of tradition and thought and aspirations with a few spin doctors and a few tame journalists."

'No chattering classes'

Mr McCartney denied that the government's policies were aimed at satisfying the "chattering classes" - but he added that Labour could not undo in 1,000 days "what the Conservatives did in 18 years".

"We can understand why people [within the party] are frustrated," he told the BBC.

"They are frustrated because they joined the Labour Party because they believe in change.

"Everyone who joins the party believes in change, whether they joined last year or 20 years ago."

Mr McCartney said that disquiet among the Labour grassroots was unfounded as the government was delivering on social policy including the minimum wage, working families tax credits and a minimum income guarantee for pensioners.

And he said that ministers remained close to their roots.

"I live in the North West in a mining community, a community that was battered and abandoned by the Conservative Party.

"I can understand the frustration when you can't get work and there are no employment opportunities.

"But this first Labour government is laying the foundations for the next term of office.

"We cannot undo in 1,000 days what the Conservative Party did in 18 years."

'Century of advances'

In a separate article for BBC News Online, Prime Minister Tony Blair insisted that if Labour did not exist today, it would be as necessary to invent it now as it was in 1900.

Arguing in his BBC News Online article that Labour had been responsible for the "greatest social advances" of the past 100 years, Mr Blair said that the party's success rested on the two "great strengths" of its members and values.

"It is our members' deep roots in the wider community that have given this party such strong life even when out of government nationally," he writes. "But there remains a great deal more to do.

"While the founders of the Labour Party would be astonished how much has changed in the world and the opportunities that now exist, they would be horrified, too, at what has not changed."