Oil futures and refined fuel benchmarks climbed on Friday and into Saturday as traders tracked tightening supply signals and widening spreads across global crude grades.Both West Texas Intermediate and Brent posted strong gains.As of 10:24 am in Tokyo on May 16, US benchmark WTI crude was up $4.25 to $105.42, a 4.2% gain. Brent crude, the international benchmark, rose $3.54 to $109.26, up 3.35%.Over the week, Brent crude climbed by 7.84%, while WTI jumped by 10.48%.Gulf marker Murban crude traded at $108.00, up 3.15%, while Dubai crude was at $102.61, up 0.25%. Oman crude on the Dubai Mercantile Exchange was little changed at $104.78.The OPEC basket posted one of the session’s largest moves, up $7.43, or 6.9%, to $115.09, reflecting broad strength across member export grades.Refined products also advanced. US gasoline futures rose 2.67% to $3.702 per gallon, while heating oil gained 3.78% to $4.053. Natural gas futures were up 2.28% at $2.960.In North America, WTI Midland climbed 3.5% to $106.64, and Louisiana Light rose 1.42% to $104.52.However, some inland US grades lagged: Mars crude fell 3.51% to $116.98, and Domestic Sweet at Cushing dropped 6.55% to $91.25.Among other international grades, Russia’s Urals slipped 0.81% to $96.72, while Western Canadian Select edged up 0.17% to $88.82. India’s crude basket rose 0.24% to $109.31, and Mexico’s basket was marginally higher at $104.46.The divergence between coastal, export-linked grades and inland U.S. crudes suggested regional bottlenecks and shifting export economics, even as headline benchmarks rallied.Traders said the broad advance reflected expectations of tighter physical supply and strong refining margins heading into the Northern Hemisphere summer driving season.