BAGHDAD Iraq criticized U.S. efforts to extend a six-month oil-for-food deal with the Untied Nations to an 18-month timeframe. State-run Al-Iraq newspaper said the attempt ``is a new American ploy and part of an aggressive pursuit'' to prolong UN trade sanctions on Iraq. Iraq is allowed, under a Dec. 1996 UN Security Council deal, to sell limited oil worth $2 billion each six months to buy food and medicine for its people.