* Stocks set to open near record highs * Markets focused on ISM manufacturing index due at 1400 GMT * U.S. payrolls report due Friday to be key influence By Ellen Freilich NEW YORK, April 1 U.S. Treasuries prices slipped on Monday after three straight weekly gains, under pressure from upbeat economic data released late last week when markets were closed and from recent strength in equities. The benchmark S&P 500 stock index and the Dow Jones Industrial Average ended last week at all-time closing highs and futures pointed to a flat open on Monday. "There was a brief sell off overnight due to the fact that the S&P 500 stock index is holding in near its all time high, signaling further 'risk on,'" said Tom di Galoma, managing director at Navigate Advisors LLC in Stamford, Connecticut. Trading resumed after a holiday-shortened week. U.S. financial markets were shut for the Good Friday holiday, and the U.S. bond market had an early market close on Thursday. Trading on Monday was subdued, with markets in most of Europe shut for Easter Monday. Ten-year Treasuries slipped 11/32 in price, their yields rising to 1.89 percent from 1.85 percent late on Thursday. U.S. financial markets were focused on the imminent Institute for Supply Management (ISM) manufacturing index at 10 a.m. EDT (1400 GMT). The index is expected to read 54.2 for March, unchanged from February. Data released on Friday, when U.S. financial markets were closed, was also somewhat bearish for Treasuries. The reports showed U.S. consumer spending rose in February and sentiment among Americans perked up in March, providing further signs of an acceleration in economic activity in the first quarter. Treasuries ended the first quarter only slightly weaker after a bid related to euro zone issues allowed safe-haven U.S. debt to erase most of the losses incurred in January and February when investors bet on a strengthening U.S. economy. Benchmark 10-year Treasuries yields reached near three-week lows by the end of last week on fear that losses bondholders and bank depositors in Cyprus are taking to restructure their banks would form a template for other euro zone nations struggling with high debt loads. Barclays' total return index on U.S. Treasuries fell 0.13 percent in the first three months of 2013, after a 0.09 percent decline in the fourth quarter of last year. Many still expect yields to gradually edge higher as the U.S. economy continues to strengthen. This week's U.S. monthly payroll number will be closely scrutinized for signs of further improvement in hiring. The report is expected to show that 200,000 jobs were added in March, according to the median estimate of economists polled by Reuters.