THE deficit in the council's pension fund is a “significant risk” to the financial health of the borough, according to a senior officer.

The accounts reveal that the fund's net assets have fallen £105m in just 12 months.

This, along with a £228m shortfall in the fund, has forced the council to increase employer contribution rate from 18.6 per cent to 21.5 per cent over three years in an attempt to recoup the cash.

Interim Head of Finance Sarah Wood, writing in the core financial statement to the council's accounts said: “Events in the markets and wider economy in recent months have clearly added to the difficulty of achieving the council's funding targets for the pension fund.”

Cllr Lewis, deputy Conservative group leader, said the fall was due to economic conditions and hopes the value of the assets will pick up again.

But if it doesn't, he said, the borough will be in trouble in about 10 years time, when retired employers draw their pension, potentially leaving the taxpayer with a huge bill.

In March the then finance cabinet member Keith Rayner said the pension fund deficit will not affect frontline services.