Iran is unable to locate all of the mines it placed in the Strait of Hormuz, curtailing its ability to fully open the critical waterway, according to a report published Friday.

Anonymous US officials told the New York Times that Iran is also unable to remove the mines it placed, complicating efforts to reopen the waterway, a key demand of the Trump administration.

Iran used small vessels to lay the mines in March, shortly after the US and Israel launched strikes across the country on Feb. 28, according to the newspaper. Iran's mines, as well as its missile and drone attacks on vessels in the region, have effectively closed the waterway, sending global energy prices skyrocketing.

Iran has since publicly noticed some routes it believes to be safe, but its "haphazard" mine-laying effort has complicated efforts to open up additional transit routes, according to one of the US officials.

Even those mines whose locations were recorded when they were laid may have floated away from their original locations, while others might not have been recorded at all, the Times reported.

The story came less than 24 hours before Iran and the US are set to convene critical talks in Pakistan focused on brokering a permanent end to the war.

US President Donald Trump announced Tuesday that he agreed to a two-week ceasefire with Iran, and has repeatedly voiced optimism at the possibility of concluding the conflict. (Anadolu Agency)