The UK's Pension Protection Fund, a cash pot set up as a safety net for workers whose pension funds fail, has rescinded a series of levy rebates it granted in September to about 40 companies, meaning they will be stung for millions of pounds in extra payments.

The PPF is funded through a levy on all pension schemes. Companies are charged according to the risk of their funds going under and their members being transferred to the PPF, meaning high-risk funds pay more.