Oil prices climbed on Friday but were on track for a weekly loss as investors doubted the prospects of a breakthrough in US-Iran peace talks. Brent crude futures rose $1.66, or 1.6%, to $104.24 a barrel by 0405 GMT, while US West Texas Intermediate futures were up $1.11, or 1.2%, at $97.46. On a weekly basis, Brent was 4.6% lower and WTI was down 7.6%, with prices fluctuating sharply as expe