Six empty Saudi oil tankers have abandoned plans to transit the Bab el-Mandeb Strait and are instead sailing south around the Cape of Good Hope, according to vessel-tracking data.

The vessels turned away in the Arabian Sea after Houthi forces in Yemen issued threats against Saudi shipping and carried out attacks on tankers in the Red Sea. The longer route around Africa is expected to add at least two weeks to their journeys compared with the normal passage through the Red Sea toward the Suez Canal.

Tracking information shows the tankers signaling destinations such as Gibraltar or the South African ports of Durban and Algoa Bay, both common refueling stops.

At the same time, more than half a dozen other empty very large crude carriers (VLCCs) are heading to Egypt’s Sidi Kerir terminal to load Saudi crude. Saudi Arabia has resumed shuttling oil from its Yanbu terminal on the Red Sea to Egypt’s Ain Sukhna port, then moving the cargoes overland via the SUMED pipeline to Sidi Kerir for export.

The moves reflect a renewed effort by Saudi Arabia to keep crude flowing while avoiding the southern Red Sea chokepoint. At least one laden Saudi tanker bound for Asia has already been forced onto the much longer route via the Suez Canal, the Mediterranean, and around Africa.

The diversions follow last week’s Houthi announcement of a blockade targeting Saudi vessels in the Bab el-Mandeb and subsequent attacks that disrupted Red Sea tanker traffic.