The Government was today urged to legislate to stop companies ending or diluting occupational pension schemes.
Unions have become alarmed at the number of firms announcing an end to final salary pension schemes.
The plea from trade union Amicus came amid warnings of a "silent revolution" in the world of work.
Amicus said if measures were not taken to protect occupational schemes, future generations of workers would face "certain poverty" in their old age.
General secretary Roger Lyons said in a letter to the Prime Minister that there was an accelerating trend away from final salary pension schemes, often leading to a substantial cut in employers' contributions.
"There is a silent revolution going on in the world of work. Employers are turning back a century of progress in pension provision."
He called on the Government to strengthen workers' rights to a decent occupational pension.
Comments: Our rules
We want our comments to be a lively and valuable part of our community - a place where readers can debate and engage with the most important local issues. The ability to comment on our stories is a privilege, not a right, however, and that privilege may be withdrawn if it is abused or misused.
Please report any comments that break our rules.
Read the rules hereComments are closed on this article