Under the 1892 treaty, the trucial sheikhs agreed not to dispose of any territory except to the British and not to enter into relationships with any foreign government other than the British without their consent. In return, the British promised to protect the Trucial Coast from all aggression by sea and to help in case of land attack. The Exclusive Agreement was signed by the Rulers of Abu Dhabi, Dubai, Sharjah, Ajman, Ras Al Khaimah and Umm Al Quwain between 6 and 8 March 1892. It was subsequently ratified by the Governor-General of India and the British Government in London. British maritime policing meant that pearling fleets could operate in relative security. However, the British prohibition of the slave trade meant an important source of income was lost to some sheikhs and merchants.