On the Tokyo foreign exchange market on Monday, the yen's value against the dollar fell to the upper 149-yen range, the lowest level since October of last year.

Investors sold yen and bought the dollar as the US government shutdown was narrowly averted on Saturday. The US Congress enacted a bill that keeps funding the government for the time being.

As of 5 p.m. on Monday Japan time, the dollar was being traded at 149.74 to 149.76 yen. The yen was down nearly a yen from Friday.

The euro was trading from 158.31 to 158.35 yen. The yen fell 0.53 yen from Sunday.

Market sources say investors are likely to sell more yen on expectations of a wider gap in interest rates between Japan and the United States as the Fed hinted at a continued tight money policy.

They also say nervous traders anticipate possible market intervention by the Japanese government and the Bank of Japan, as the yen approaches the 150-yen mark.