Oil prices rose for a fourth day to a seven-year high as an outage on a pipeline from Iraq to Turkey increased concerns about an already tight supply outlook amid worrisome geopolitical troubles in Russia and the United Arab Emirates.

Brent crude futures rose US$1.44, or 1.7 percent, to US$88.95 a barrel at 0230 GMT (10.30am Malaysia time), adding to a 1.2 percent jump in the previous session. The benchmark contract climbed to as much as US$89.05, its highest since Oct. 13, 2014.