TOKYO, March 3 : Fresh market volatility triggered by the Middle East conflict has heightened the chance the Bank of Japan will hold off on raising rates in March, sources said, as policymakers need more time to gauge the impact on the economy. The only factor that may prod the BOJ to raise rates at its March 18-19 meeting would be sharp falls in the yen, which has already taken a hit following the U.S. strikes on Iran, sliding closer to the key 160 mark on strong investor appetite for the safe-