The International Maritime Organisation (IMO) is examining controversial new regulations announced by Turkey for shipping through the Bosporus. The London-based IMO’s maritime safety committee took up the matter during a mid-May meeting after objections from Russia and other countries who allege that the Turkish measures, due to start on 1 July, violate the 1936 Montreux Convention.

The new regulations include restrictions on the passage of vessels more than 200 metres in length and a requirement for all vessels carrying potentially dangerous cargoes to give advance notice to Turkish authorities. Turkey fears the congested Bosporus is ripe for an ecological disaster which could threaten Istanbul and its 10 million inhabitants. The Bosporus was closed for about a week in March after a Greek Cypriot tanker collided with a freighter and burned for days.