Sky sources understand the credit ratings agency Moody’s will announce downgrades to major world banks, including UK lenders, as early as tonight. City editor Mark Kleinman has learned that confirmation is expected shortly after the US markets close for business this evening – potentially adding billions of pounds to the funding costs of the institutions affected. He believed RBS, Barclays and HSBC were among the banks under scrutiny amid the pressure facing the industry from the effects of the global financial crisis. The net could also be cast across the English Channel to France and its two big banks Societe Generale and BNP Paribas he said, while Wall Street banks Goldman Sachs and Morgan Stanley may have been on the radar too. Kleinman said the move, which may affect up to 18 lenders, was part of a wider reassessment of the health of the global banking industry by the agency. The major ratings agencies have rushed to downgrade banks across the Continent in recent months, particularly as the eurozone’s problems have intensified. A cut last month to the credit rating of Santander UK, the Spanish-owned lender, triggered speculation about the safety of customers’ savings which was quickly dismissed by the bank. The latest wave of downgrades will bring many of the other UK banks in line with Santander UK and there will be no resulting impact on the security of their savings. The downgrades are expected to range in scope from one notch to two notches depending on the particular institution. Kleinman expected Barclays to face the prospect of a two notch downgrade. Bank shares lost value in late trading on the FTSE 100, with RBS the biggest faller of the main UK banks.