Oil prices extended losses Tuesday as the Bank of Japan left the stimulus program unchanged. Investors were disappointed as in its policy statement, the Bank of Japan on Tuesday failed to take steps to ease market turbulence. Some analysts had expected that the Japanese central bank would take additional measures to address bond volatility. The Organization of Petroleum Exporting Countries (OPEC) added more pressure on oil prices when it disclosed that its members increased production by 106,000 barrels daily to 30.57 million a day last month, led by gains in Saudi Arabia. In its monthly market report for May, OPEC kept its world oil demand forecast for 2013 almost unchanged, while saying it expected world demand this year to reach 89.65 million barrels per day, a slight drop from the forecast of 89.66 million barrels per day in its previous monthly report. On the economic front, U.S. small-business owner confidence rose for the second consecutive month, according to the Index of Small Business Optimism run by the National Federation of Independent Business, which went up to a final reading of 94.4 in May. Wholesale inventories, a key component of gross domestic product changes, advanced 0.2 percent in April, which was in consistent with market expectations, U.S. Commerce Department said Tuesday. Light, sweet crude for July delivery lost 39 cents, or 0.4 percent, to settle at 95.38 dollars a barrel on the New York Mercantile Exchange. Brent for July delivery went down 99 cents, or 0.95 percent, to close at 102.96 dollars a barrel.