World oil prices fell on Monday. Brent crude fell by US$3.04 or 4.9% to US$59.54 a barrel in response to speculation that a nuclear deal between Iran and Western nations could lead to an easing of sanctions that had restricted Iran's oil exports. Meanwhile US Nymex crude fell by US17c or 0.3% to US$49.59 a barrel, with prices supported by expectations of a slower build in stockpiles this week.