Payments from the UK government ensured Spain's neutrality in World War IIEl País in English

"On June 4, 1940, the British ambassador to Madrid, Sir Samuel Hoare, sent an urgent encoded “personal” message to British Foreign Secretary Viscount Halifax. In it he revealed that there were signs Spain might soon abandon its neutral position and enter World War II on the side of the Nazis. The moment to act had arrived, he concluded, adding that he believed he had a safe way to access the best-placed ministers.
That method, revealed in one of over 400 documents recently declassified by Britain’s National Archives, was “to influence policy decisively and ensure Spain’s neutrality” by paying bribes for which he said he might “need up to 500,000 pounds.”"
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