Two Pakistan-flagged oil tankers carrying Saudi crude have sailed through the Red Sea and Bab al-Mandeb without incident, despite the Houthi blockade against Saudi Arabia, according to maritime intelligence company Windward, Al Jazeera reports.

The Aframax crude tankers loaded oil at Saudi Arabia’s Yanbu port before travelling back to Pakistan with their tracking systems switched on, Windward said.

Since the Houthis announced the blockade on July 20, Saudi-linked tankers, excluding vessels affiliated with China, have either been attacked or diverted around the Cape of Good Hope, the company said.

The crossings came days after the Foreign Office (FO) warned the Houthis that any attack on a Pakistani-flagged vessel would be treated as a threat to the country’s security.