Problem loans at the nation's 64 regional banks rose 17.7 percent to 9.8 trillion yen during fiscal 2000 as borrowers fell delinquent and banks made more stringent assessments of loans, the Association of Regional Banks said Wednesday.

Loans categorized as "troubled but not yet in default" soared 60.4 percent to 2.8 trillion yen. Banks increased writeoffs 14.4 percent to 1.3 trillion yen, causing 15 of the 64 regional banks to report net losses.

During the previous year, five banks reported net losses.