The Pakistani rupee extended its marginal gains against the US dollar on Friday. The local unit closed the day at 277.41, a gain of Re0.01 against the greenback. On Thursday, the Pakistani rupee settled at 277.42 against the dollar. Moreover, the Japanese yen clung to its gains against the US dollar on Friday and was on track for its strongest week in more than a month. The dollar index, which measures the greenback against a basket of currencies including the yen and the euro, was flat at 99.01, leaving the euro flat at $1.1625 and sterling at $1.3527. Furthermore, oil prices rose on Friday, heading for their steepest weekly gain since mid-July. Brent crude futures rose 54 cents, or 0.6%, to $96.06 a barrel by 0100 GMT, while US West Texas Intermediate crude futures climbed 80 cents, or 0.9%, to $92.10. On a weekly basis, Brent rose 7.6% and WTI was 10.4% higher, set for the highest gains since the week ended July 20.