Oil futures kicked off the second half of the year with sharp losses on Monday, as investors got rattled by a weekend tweet from President Donald Trump who hinted of a big potential production increase from Saudi Arabia. August light, sweet crude on the New York Mercantile Exchange CLQ8, -0.28% was recently down 63 cents, or 0.9%, to $73.51 a barrel. September Brent LCOU8, -0.86% fell around $1, or 1.2%, to $78.25 a barrel. WTI crude notched another finish at its highest since November 2014 on Friday, while also logging strong weekly, monthly, quarterly and first-half 2018 gains. Prices have driven higher by long-running efforts by the Organization of the Petroleum Exporting Countries to reduce production, anticipated increases in demand and supply disruptions. Brent crude logged its best finish since May on Friday, after also seeing strong gains in the first half of the year.via