Scottish Widows, one of the UK's best-known pension providers, is closing its own final salary pension scheme to new staff.

The company said the value of pensions for new recruits will no longer be guaranteed and will in future depend on the strength of the stock market.

Managers said the decision underlined the serious nature of the pensions crisis.

The union Amicus said the move amounted to "a pensions robbery".

Some people will do better and some may do worse - but if the markets are good then they could do very well

David Graham Scottish Widows

Scottish Widows is one of many big employers, including the rival pension company Prudential, which have closed final salary schemes to new employees.

Final salary schemes have become increasingly expensive for employers.

When the stock market was doing well, many pension schemes' investments went into surplus and some employers took time off from paying contributions.

Now the market is down, employers have the choice of contributing more, or closing the scheme to anyone not already in it.

Companies are also blaming new accounting rules and government red tape for their decisions to close schemes.

'Unforgivable' move

Scottish Widows said its scheme would be closed to employees who were recruited after 1 January 2003.

The decision has been criticised by unions.

Amicus said it would campaign to stop the company from pressing ahead with its plans.

Dave Fleming, of the union Amicus, likened the news to "a pensions robbery" and said workers were concerned about the future.

He said: "It's not just in the insurance industry, although there is an irony that we are facing this now and facing it in more than one company.

"We are very concerned that the dissolution of pension schemes for employees is something in our society that is unforgivable."

David Graham: "Efficient and generous"

But Scottish Widows' David Graham said the scheme was "efficient and generous".

"They (employees) can contribute to it themselves and it's part of an overall package which will allow flexibility," Mr Graham said.

"The benefits will, of course, be dependent on the market on retiral.

"Some people will do better and some may do worse - but if the markets are good then they could do very well."

Pensions' crisis

Personal finance expert Andy Cowan said it was not in employees' interests for final salary pension schemes to be scrapped.

He said final pension schemes shielded employees from the stock market.

The government has come under fire over the past year for failing to tackle the growing crisis in pensions.

Ministers have pledged to publish a green paper by the end of the year.

Raising the retirement age and abolishing tax-free lump sums are two options under discussion.