SINGAPORE, May 24 (AFP) - The US dollar ended lower Monday against the euro and higher against the yen in quiet Singapore trading, dealers said. The dollar opened trading here at 123.85 yen and ended at 123.93. The euro started trade at 1.0568 dollars and ended higher at 1.0588, acording to rates from Banque Nationale de Paris. A dealer with the French bank said there was some euro buying when London opened after the market failed to push down the single European currency, languishing near record low levels. The British pound fell to 1.6005 dollars from the opening level of 1.6010. Against key Southeast Asian currencies, the dollar ended higher at 8,075 Indonesian rupiah from Friday's close of 8,045, 1.7226 Singapore dollars from 1.7198 and 37.08 Thai baht from 37.00.  