Commercial traffic through the Strait of Hormuz and the Bab el-Mandeb Strait plummeted on Wednesday, with tracking data showing only three vessels crossing the critical waterways.
The sharp contraction follows claims by Houthi militants that they attacked a Saudi-owned tanker, signaling a renewed intensification of hostilities in the region.
This represents a severe tightening of transit activity compared to recent days, as shipping operators increasingly avoid the high-risk corridors.
The near-freeze in vessel movements underscores the persistent vulnerability of global energy supply routes.
With the Strait of Hormuz handling roughly a fifth of the world's oil consumption and the Bab el-Mandeb serving as a vital artery for container and bulk trade, such a drastic drop in traffic volume poses immediate risks to supply continuity.
Markets are likely to price in heightened disruption premiums as the window for safe passage narrows.