The downgrade of Bermuda’s credit rating by Fitch will cost taxpayers $15.5 million in extra interest payments on this week’s Government bond issue, according to the opposition One Bermuda Alliance (OBA).In a press conference today, Shadow Finance Minister Bob Richards blamed “mismanagement of the public purse” for the downgrade and claimed that Fitch had cast doubt on Government’s credibility and lack of a plan to deal with the mounting public debt.Yesterday, ratings agency Fitch downgraded Bermuda sovereign bonds by one notch to AA from AA+ as Government raised $475 million through selling ten-year bonds, which will give investors a 4.13 percent rate of return.“Before the downgrade, existing Bermuda Government bonds yielded 3.81 percent,” Mr Richards said. “After the downgrade the new issue yield was 4.138 percent, an increase of 0.33 percent. With the issue size of $475 million the cost of the downgrade to Bermuda taxpayers was $15.5 million.”Mr Richards said Fitch’s “damning report” had issued a thinly veiled threat that without a more disciplined approach to public finances, another negative judgement would follow.And he claimed that Government was leading Bermuda “into a deeper and deeper financial hole — a hole that will take decades to climb out of”.Mr Richards, who appeared at the press conference alongside OBA leader Craig Cannonier, said a combination of pro-growth policies and the cutting of wasteful Government spending was the key to getting out of the current fiscal predicament.He also stated that an OBA government would achieve spending cuts without redundancies, rather reducing the public sector workforce through attrition.