On 17 June 1940, three days after the Fall of Paris and the day Marshal Petain asked for an armistice, Butler had a mysterious meeting in St James's Park with the Swedish envoy Dr Björn Prytz. The meeting continued for a few minutes in the Foreign Office, during which Butler conferred briefly with Lord Halifax in his office. Prytz reported back to Stockholm that Butler had declared that British policy must be determined by "common sense not bravado" (the phrase was repeated in English) and that he had "assured me that no opportunity for reaching a compromise (peace) would be neglected if the possibility were offered on reasonable conditions."