Belgium’s credit rating was cut one step to AA by Standard & Poor’s, which said bank guarantees, lack of policy consensus and slowing growth will make it difficult to reduce the euro region’s fifth-highest debt load.

The rating was lowered from AA+, with a negative outlook, London-based S&P said yesterday in a statement. The action by S&P is the first downgrade for Belgium in almost 13 years and puts its credit ranking on a par with the S&P local-currency ratings of the Czech Republic, Kuwait and Chile.

Belgium’s borrowing costs have surged to the highest level in 11 years in the past two months after the nation’s government agreed to buy Dexia SA’s Belgian bank unit and guarantee part of the crisis-hit lender’s liabilities for 10 years. Investors continued a selloff in Belgian bonds after six-party coalition talks ran aground this week as Liberals and Socialists clashed over how to cut the budget deficit.

“One cannot ignore the current political crisis that Belgium is facing, but apart from this, this rating cut also illustrates how banking-sector issues can reverberate on the sovereign,” said Thomas Costerg, an economist at Standard Chartered Bank in London. “The question is whether other European countries might follow, given rising tensions throughout the banking sector.”

Belgium follows Slovenia, Spain, Italy, Ireland, Portugal, Cyprus and Greece as euro-area countries having their credit rating cut this year. The country of 10.8 million people, whose capital, Brussels, is home to the European Commission and the North Atlantic Treaty Organization, last had its credit standing lowered in December 1998 by Fitch Ratings.