Japan is prepared to consider coordinated currency intervention with the United States again if market conditions require it, Finance Minister Satsuki Katayama said, reaffirming the principles behind the July 31 operation. The yen weakened beyond 158 per dollar after the Bank of Japan raised rates to a 31-year high on Friday, a move that failed to convince investors that more aggressive tightening was imminent. Japanese authorities also conducted overseas-market rate checks, which are often viewed as a precursor to intervention; the yen's initial recovery was short-lived.