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May 26 (Reuters) - Australia stocks ended lower on Friday, battered by a downturn in commodity prices - especially oil - after OPEC's modest extension of output curbs disappointed investors who had hoped for more.
The S&P/ASX 200 index slipped 37.9 points or 0.66 percent to 5,751.7 at the close of trade. On the week, however, it rose 0.38 percent.
BHP Billiton, the world's biggest miner, posted its sharpest intraday slide in three weeks, hit by falling oil prices and compounded by iron ore prices that appeared to be poised for a third weekly fall in four.
The metals index wilted 1.46 percent at close.
Commonwealth Bank, Australia's biggest, was the top loser on the index, off 1.38 percent.
ANZ Banking slid 1.5 percent, while the other two of the 'Big Four' fell around 0.5 percent each.
New Zealand's benchmark S&P/NZX 50 index recouped morning session losses and closed 0.09 percent or 7.1 points higher, to finish the session at 7,441.57, helped by healthcare stocks.
Fisher and Paykel Healthcare was the top performer, up 2.22 percent. (Reporting by Aparajita Saxena in Bengaluru)