By 1937, there were still five Gulf sheikhs due to sign oil concession agreements.

Following British recognition of Sheikh Hamad, the second son of Sheikh Abdullah as the Heir Apparent of Qatar, Sheikh Abdullah signed the first Oil Concession Agreement with the Anglo-Persian Oil Company on 17 May 1935.

In 1937 Holmes was instructed by Petroleum Concessions Ltd - an associate company of IPC - to complete oil concession agreements with the sheikhs of the Trucial Coast and the ruler of Oman but he proved dilatory and had to be relieved through ill-health.