Amicus said a new mood of militancy was sweeping British workplaces in what it describes as the "great pension robbery."

We will not stand by and watch employers steal our members retirement income nor force a future generation into poverty in old age

Roger Lyons Amicus general secretary

A poll of the union's members, to be published at its annual conference in Blackpool on Saturday, reveals overwhelming support for strike action.

The news follows growing concern about the number of final salary pension schemes closing.

A recent poll revealed plans by a quarter of small firms to wind up or close schemes within the next year.

Bryan Freake, a pensions expert who works for Amicus, told BBC News: "Members are increasingly recognising the value of those pensions.

'Payback time'

"Too often, they have taken their pensions for granted, but the value of a good pension scheme can be 20% of their pay.

"If employers threaten to take that away, it's hardly surprising that employees are going to stand up for their rights, because the law gives them very little protection."

Mark Baker, an engineer at Holywell UK, had his final salary scheme replaced by a money purchase plan and says he and his colleagues fear for the future.

He told the BBC Radio 4's Today programme: ""We see the situation these days where a lot of people have a very poor income in retirement.

Roger Lyons of Amicus wants to protect workers

"You get your pay for attending and when you retire, your pension is basically your deferred pay."

According to the Amicus report, as many as 90% of union representatives said they and their colleagues will strike if their employer tries to close their scheme or reduce contributions.

The closures have every possibility of becoming a strike issue.

Final salary pensions, which are based on years of service and a worker's final salary, are being replaced with more risky and less generous money purchase schemes.

Elderly poverty

According to additional findings from Amicus, a typical scheme will generate a pension around 40% lower at age 60 than a typical final salary scheme.

And employers are not only closing final salary schemes, but also reducing their contributions.

Mr Lyons, who will address the conference on Saturday, said: "In this era of low inflation and mass redundancies, pensions have replaced pay as the main area of industrial conflict," he said.

"We will not stand by and watch employers steal our members retirement income nor force a future generation into poverty in old age.

"Amicus will give full support to any of our members who wish to make a stand against the great pension robbery."

Mr Lyons told Today he wanted the government to force employers to pay a minimum "safety net" of contributions at a level such as 5%.

Shadow work and pensions secretary David Willetts said anger should be directed at the Chancellor Gordon Brown.

He added: "The government has deprived pension funds of some �5bn a year. This is further evidence of the crisis facing our funded pensions."