TOKYO (Reuters)  The United States dollar fell to its lowest in eight months against the yen on Monday, as investors unwound short yen positions and as expectations that Japan will intervene at these levels receded.

The dollar dropped as low as 88.23 yen, its weakest since late January when it hit a 13-year low of 87.10 yen.

Japan has intervened in the currency market in the past to weaken the yen as this helped keep its competitive advantage in global trade.

Large margin calls on the pound and yen have also been behind the yen buying. The pound fell sharply to $1.5770, its lowest since late May, breaking below support for sterling at around $1.5800. It was hammered against the yen, falling 1.6 percent and briefly dropping below the 140 yen mark, its lowest since late April.