NEW YORK, May 31 (Xinhua) -- The U.S. dollar weakened in late trading on Monday as market participants awaited a slew of key economic data.

The dollar index, which measures the greenback against six major peers, slid 0.21 percent at 89.8378.

In late New York trading, the euro increased to 1.2227 U.S. dollars from 1.2196 dollars in the previous session, and the British pound was up to 1.4202 dollars from 1.4192 U.S. dollars in the previous session. The Australian dollar increased to 0.7737 U.S. dollar from 0.7709 dollar.

The U.S. dollar bought 109.49 Japanese yen, lower than 109.80 Japanese yen of the previous session. The U.S. dollar decreased to 0.8988 Swiss franc from 0.8993 Swiss franc, and it fell to 1.2050 Canadian dollars from 1.2078 Canadian dollars.

"Today is Memorial Day. So there are hardly any data publications in the US. For the rest of the week there is some interesting U.S. data due for publication which might provide some momentum to the USD exchange rates," Ulrich Leuchtmann, analyst at Commerzbank Research, said in a note on Monday.

Traders will look closely to the U.S. manufacturing PMI (Purchasing Managers' Index) released by the Institute for Supply Management (ISM) on Tuesday, the ISM services index on Thursday and the Bureau of Labor Statistics' monthly labor market report on Friday.