By the Anglo-Turkish Convention of 1913, the Ottomans agreed to renounce their claim to Qatar and withdraw their garrison from Doha. However, with the outbreak World War I, nothing was done to carry this out and the garrison remained in the fort at Doha, although its numbers dwindled as men deserted. In 1915, with the presence of British gunboats in the harbour, Abdullah bin Jassim Al Thani (who was pro-British) persuaded the remainder to abandon the fort and, when British troops approached the following morning, they found it deserted.