Oil headed for a second weekly increase as OPEC and other producing nations maintained they would achieve their target of cutting production to reduce bloated global inventories and stabilize the market. Front-month futures in New York are up 2.3 percent for the week, set for the biggest advance since Dec. 2. OPEC and other producers are due to reach the 1.8 million-barrel-a-day reduction target next month, Algeria’s Energy Minister Noureddine Boutarfa said Thursday.