New Delhi, Aug. 21 -- Crude oil prices are on track to post a second consecutive weekly gain as hopes for a diplomatic breakthrough in the Middle East faded after the US announced plans to impose sweeping sanctions on Iran, seeking to economically isolate Tehran and pressure it to accept Washington's conditions.

International benchmark Brent crude futures advanced another 6% this week, with prices topping $94.71 per barrel, marking their highest level in nearly a month. If the rally is sustained through the end of the month, it would also mark the second consecutive month of gains, building on a 20.5% jump in July.

Traders are now awaiting further details of the US campaign to isolate Iran's economy, with no apparent end in sight to a c...