Churchill acknowledged that Franco held the keys to Gibralter and could have at any time made that fortress untenable for Great Britain. He said that while Franco always acted in his self-interest he was grateful that included nuetrality.
Churchill went so far as to play on the fact that Franco and the Spanish acted firstly in their own interest. So much so that despite the fact that the British are essentially broke they managed to come up with a $10 million (USD) bribe to the Spanish generals to keep them out of the war. This was arranged through Franco’s personal banker, Juan March and the money was sent to Swiss bank accounts (I don’t have the exact date of this but it took place sometime between now and May of next year).