China   government has ordered its major refiners to halt diesel and gasoline exports amid rising tensions in the Persian Gulf. Concerns over further escalation around Iran and ongoing regional instability have kept investors on edge, while shipping through the Strait of Hormuz, a critical chokepoint, has been disrupted. Efforts to ease market worries, including proposals for vessel insurance and naval escorts, have so far failed to calm investors, who are closely monitoring developments for signs of a prolonged conflict.