As few as a dozen ships have navigated the de facto blockade in the Straight of Hormuz, following a ceasefire agreement late Tuesday between the U.S. and Iran in which Tehran is supposed to reopen the key shipping channel, in which 20% of the world's oil passes. 

Data from the U.N.'s Trade and Development organization shows that on an average day, prior to the United States' war wih Iran that began Feb,. 28, 129 vessels would pass through the strait, CBS News reported. 

The strait is also a primary artery through which liquefied natural gas and petrochemicals pass.

In a post on Truth Social on Thursday evening, President Trump expressed displeasure with Iran's level of compliance with the agreement, stating that the country is doing a "very poor job" of letting ships through.