Churchill definitely was on our side in Winter War and after that but the British foreign policy...well, I would not really say so...

"Compared to the early spring, during the summer of 1940, Finland wasn't high in importance in British foreign policy. To gain support from the Soviet Union, Britain had appointed Sir Stafford Cripps, from the left wing of the Labour Party, ambassador to Moscow. He had openly supported the Terijoki Government during the Winter War and he wondered to Ambassador Paasikivi 'didn't the Finns really want to follow Baltic Republics and join the Soviet Union?'. He also dismissively called President Kallio "Kulak" and Nordic social democracy "reactionary". The British Foreign Office had to apologize for his language to Ambassador Gripenberg."

http://en.wikipedia.org/wiki/Interim_Peace

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