Both the Royal Navy (RN) and Royal Canadian Navy (RCN) were in desperate need of warships for escort duty on the transatlantic convoy routes. The Canadian prime minister, William Lyon Mackenzie King, helped initiate discussions between the American and British governments on a solution to this problem. Ultimately, the Americans agreed to transfer 50 destroyers to the RN and RCN in return for leases on British naval bases in North America, including three in Newfoundland. The British and American governments finalized the agreement on 5 September 1940. The RCN received seven destroyers under the arrangement and, as a result, was able to increase the size of its convoy escort units.