BT, the UK telecoms group, has become the second FTSE 100 company in a week to unveil a dramatic turnaround in its pension fund, having swung from a deficit of £2bn (€2.9bn) to a surplus of £1.5bn in the 12 months to September 30.

The company said the improvement was down to an £840m cash payment by the company to address the deficit, combined with rising bond yields, which reduce liabilities, and a good return on scheme investments.