Oil markets stabilized on Friday amid OPEC supply cuts and tensions in the Middle East, after posting their steepest falls since the start of the year earlier in the week on the back of a global economic slowdown and swelling fuel inventories. U.S. West Texas Intermediate (WTI) crude futures were up 36 cents, or 0.6 percent, at $58.27 per barrel. The Organization of the Petroleum Exporting Countries (OPEC) has led supply cuts since the start of the year aimed at tightening the market and propping up prices. ANZ said U.S. sanctions on Iran's and Venezuela's oil industries would likely further reduce crude exports from OPEC, of which both countries are members. But Friday's firmer prices could not make up the much bigger slumps from earlier in the week, which have put crude futures on track for their biggest weekly losses this year. From mid-week, rising oil inventories in the United States started weighing on prices.