Initially, Royal Navy ships were to shadow and question Beira-bound tankers, and were only allowed to forcibly divert a tanker away after Britain obtained permission from its flag state. However, in the event that permission was granted, British warships were only allowed to demand it change course in the name of its flag state, and fire a shot across the bow if it did not work. The use of force was not authorised, and if the tanker absolutely refused to comply, the shadowing warship could take no more action and only follow it to within Mozambique's six-mile territorial limit.