 After the German occupation of Denmark and Norway, Britain occupied Iceland and the Faroe Islands, establishing bases there and preventing a German takeover.It was in these circumstances that Winston Churchill, who had become Prime Minister on 10 May 1940, first wrote to President Franklin Roosevelt to request the loan of fifty obsolescent US Navy destroyers.This eventually led to the "Destroyers for Bases Agreement" (effectively a sale but portrayed as a loan for political reasons), which operated in exchange for 99-year leases on certain British bases in Newfoundland, Bermuda and the West Indies, a financially advantageous bargain for the United States but militarily beneficial for Britain, since it effectively freed up British military assets to return to Europe.