The US dollar was slightly weaker against the yen in thin trading here with most investors hesitant to make aggressive positions while the US market is shut for a public holiday, dealers said. The dollar rose to a high of 118.37 yen in early Asian deals as importers bought the greenback for commercial requirements, but gains proved to be short-lived due to a dearth of follow-up buying, analysts said. "Few market players here are willing to trade aggressively ... this is because of the US holiday today," said Harry Ida, senior currency analyst at Thomoson Financial's IFR Forex Watch. Athena FX director and analyst Takashi Kudo said the US unit was caught between firm dollar demand from mutual funds and offers near and above 118.50 yen level from exporters and institutional investors repatriating their dollar-denominated earnings ahead of the closing of their books at end-March. At 1.28 pm (0428 GMT), the dollar stood at 118.05 yen, after moving in a range of 117.93-118.37 yen during Asian trading hours. More than four hours earlier in Sydney, it was at 118.21 yen compared to 118.18 yen in late New York trade on Friday. The euro was at 1.1964 usd, compared to 1.1936 in Sydney and 1.1940 in New York. "This week's focus will be the January US consumer price index, due Wednesday, as the market is awaiting the key inflation data," Thomson Financial's Ida said. Athena FX's Kudo said investors are also looking forward to the release tomorrow of the minutes of the Federal Open Market Committee meeting in January to gauge up to when the Fed will hike rates after another expected 25-basis point increase next month. Last week, new Fed Chairman Ben Bernanke told Congress in his first testimony that more rate hikes may be needed because of the threat of higher inflation, but suggested they will become "increasingly dependent" on economic data.