US-Iran war, Aug. 11 -- Oil prices extended their gains for a fourth straight session after US President Donald Trump issued sweeping new demands on Iran, casting fresh uncertainty over prospects for a deal that could facilitate the reopening of the strategically vital Strait of Hormuz.

Brent crude futures were little changed at $87.81 a barrel, while US West Texas Intermediate (WTI) crude futures remained at $82.20 a barrel. Both benchmarks had climbed more than 5% on Monday, reaching their highest levels since July 31.

US President Donald Trump has demanded that Iran compensate for the people killed in conflicts, after Tehran renewed its call for reparations as part of negotiations aimed at bringing the conflict to an end.

In a socia...