Washington, June 16 -- Recent US intelligence assessments conclude that Iran has developed the ability to effectively shut access to the Strait of Hormuz whenever it chooses, giving Tehran a powerful tool to pressure the global economy even as it moves toward a new agreement with Washington, according to sources familiar with the appraisals.

The assessments come ahead of a memorandum of understanding due to be formally signed on Friday, under which Iran and the United States are expected to begin a new round of negotiations while working to restore normal shipping through the strategic waterway.

US intelligence agencies reportedly believe that Iran's actions during the conflict demonstrated both the capability and willingness to disrupt t...