San Marino Central Bank chairman Antonio Valentini has offered to resign to safeguard the bank's reputation after a judicial probe exposed irregularities at banks in the tiny independent republic in central Italy. An investigation by magistrates in Italy into lenders Asset Banca di San Marino and Italy-based Banca di Credito e Risparmio di Romagna has exposed activities linked to tax evasion, a central bank spokeswoman said. About 10 people, including a banker with business ties to Mr Valentini, were arrested this week in connection with the investigation, which is a severe blow to San Marino's efforts to clean up its image as a loosely-regulated tax haven. Mr Valentini, who was appointed as San Marino's first central bank chairman when it was created in 2005, told Reuters his association with Stefano Venturini, a board member at both banks under inquiry who was among those arrested, was merely related to sharing some business facilities with him. "I cannot accept that my presence can be an obstacle to all that we have achieved up until now," he said.