HC Deb 04 March 1940 vol 358 c2
5. Mr. Arthur Henderson

asked the Prime Minister whether the Treaty of Mutual Assistance between His Majesty's Government, the French Government, and the Turkish Government is regarded as coming within the terms of Article 19 of the Montreux Convention, so as to permit, if desired, the passage of British and French warships through the Dardanelles Straits during the present war emergency?

Mr. Butler

In the event of the Treaty of Mutual Assistance coming into operation, Turkey would be a belligerent and would, therefore, under Article 20 of the Montreux Convention, have full discretion to permit, if desired, the passage of British and French warships through the Straits. Article 19 is, therefore, not relevant in connection with the Treaty of Mutual Assistance.