Ship movements along the Omani side of the Strait of Hormuz have dropped to a minimum, according to sources cited by Bloomberg.
The decline followed a series of vessels reversing course in the area.
At least eight ships travelling along the Omani coast reversed course, with four promptly leaving the strait via Iranian waters, the agency said.
The affected vessels included oil tankers, bulk carriers, and car carriers, according to Bloomberg.
The day before, 19 ships crossed the strait in both directions, but only one openly registered its passage via the Omani route, a source said.
The downturn may be linked to Tehran's requirement that tankers transit the strait exclusively on Iran-approved routes.