The Globe and Mail reports in its Monday edition that oil prices rose above $100 a barrel after U.S. President Trump announced a blockade of the Strait of Hormuz amid unsuccessful peace talks in the six-week-old Middle East conflict (all figures U.S.). The Globe's Eric Atkins and Jeffrey Jones write that U.S. and Iranian officials ended their negotiations in Pakistan on Sunday without reaching an agreement to end the war that began on Feb. 28, causing disruptions in global energy markets. International benchmark Brent crude was up 8 per cent at $102.80 a barrel after Asian markets opened. West Texas Intermediate gained nearly 9 per cent to reach $104.97. Prices have risen by as much as 70 per cent since the attacks by the U.S. and Israel began. Mr. Trump said on social media Sunday that the U.S. Navy will block the key trade route, intercept ships that have paid a toll to Iran and conduct de-mining operations. Iran's leaders were defiant and gave no signs they would cede control of the strait. Senior Iranian official Ali Akbar Velayati said on social media that the strait is "firmly in our hands." The failed negotiations have heightened the risk that the oil shock will drag on.