Oil traded near a one-month high after entering a bull market, while the tension between an uncertain economic outlook and efforts by Opec to restrict supplies continued to cause volatile trading. West Texas Intermediate slipped 0.5% after a rally on Wednesday brought crude’s rebound from an 18-month low in December to 23%. Prices had climbed as Saudi Energy Minister Khalid Al-Falih expressed confidence that production curbs by the Opec+ coalition would balance the market. Yet investors remain wary as they await concrete details of US-China trade negotiations, which are clouding the economic outlook.