Brent crude futures advanced $3.34, or 4.38%, to $79.5 a barrel, while U.S. West Texas Intermediate (WTI) crude gained $3.07, or 4.30%, to $74.20 a barrel. The latest rally comes after both benchmarks climbed 5.5% last week, with WTI once again trading above $74 a barrel. European natural gas futures also rose 2.5% after markets reopened following the weekend.