Warburg Dillon Read and JP Morgan have been forced into a last-minute increase in the coupon on a £150m (€248m) issue of long-term bonds for Kelda, the owner of Yorkshire Water.

The price of the new bonds, where payment is owing today, slid last week as Kelda suddenly announced it might sell Yorkshire Water, its main asset. It also revealed the sudden exit of its chief executive Kevin Bond. The move prompted concerns that the rating agencies will downgrade the bonds. To compensate investors, the coupon goes up from 6.375% to 6.625%.