The ministers boast about the number of schemes but there ain't no money

David Willetts, shadow work and pensions minister

The figures - which have been withdrawn "for further clarification" - appear to show a massive, unexplained drop in the value of occupational pension schemes in 1999.

The Tories say the confusion shows the government's pensions policy is in disarray.

They warned that millions more people will end up relying on means-tested benefits in their old age because of the failure of Labour policy.

Labour accused the Tories of trying to make political capital out of an apparent statistical error, which was being looked into by the independent Office for National Statistics.

They accused the Tories of having no pensions policy of their own.

Stakeholder 'shortfall'

The Conservatives say they want more people to take out private pensions - even suggesting at the general election that young people should be allowed to opt out of the state pension altogether.

Labour remains committed to basic state provision - but also want people to take out a second, private pension to make up any shortfall.

Shadow Work and Pensions Minister David Willetts said the government was failing to attract enough people into government-backed private schemes.

It was falling "many millions short" of its take-up target for its flagship stakeholder pensions scheme - which was meant to encourage people on middle and low incomes to save for their retirement, he said.

Companies that do not provide an occupational pension have to offer their employees a chance to contribute to a stakeholder pension fund.

But, according to Mr Willetts, nearly 80% of stakeholder schemes sold so far were "empty", with no contributions going into them at all.

Opening a Commons debate on pensions, Mr Willetts said: "The empty stakeholder is the apotheosis of Labour's pension policy; the legislation is passed, the brand name's launched, the employers comply with the new regulation, the employers are informed, the ministers boast about the number of schemes but there 'aint no money."

'Sneaking out' figures

Referring to the apparent plunge in the value of pension funds, Mr Willetts accused the government of trying to sneak out the "biggest revision to economic statistics in the history of British economic management".

Instead of having �783bn in UK pension funds, as previous figures had suggested, there was only �679bn, he alleged.

"I think we are entitled to an explanation for ministers as to why they suddenly reduced the value of the money in our pension schemes by no less than �104bn ... with no apology, no explanation, no rationale," he told MPs.

'Encourage saving'

Work and Pensions Secretary Alistair Darling brushed aside claims of incompetence over the pension fund 'error'.

And he told Mr Willetts: "We are well into this Parliament and not a single word from you as to what your policy is."

A promised consultation paper on annuities would be published on Tuesday, he told MPs.

"It will be an opportunity for people to look at options to encourage people to save more for their own retirement ... and make the right choices.

"It will maintain the principle that annuities are, for most people, the best way of ensuring that they have security in retirement.

"However, the Government is prepared to look at options for change."

Independent report

Mr Darling said that more than 637,000 stakeholder pensions had been sold.

The debate comes as an independent report says the government's "state second pension" scheme could force millions of people into the arms of the state.

The report, by consultants William H Mercer, says the government has failed to do enough to encourage workers to opt out of the state second pension and take up a private pension.