Simultaneously, Elizabeth had conveyed to Louis XV a confidential letter in which she proposed the signature of a new treaty of alliance of a more comprehensive and explicit nature than the preceding treaties between the two powers without the knowledge of Austria. Elizabeth's object in the mysterious negotiation seems to have been to reconcile France and Great Britain, in return for which signal service France was to throw all her forces into the German war. This project, which lacked neither ability nor audacity, foundered upon Louis XV's invincible jealousy of the growth of Russian influence in Eastern Europe and his fear of offending the Porte. It was finally arranged by the allies that their envoys at Paris should fix the date for the assembling of a peace congress and that in the meantime, the war against Prussia should be vigorously prosecuted. In 1760 a Russian flying column briefly occupied Berlin. Russian victories placed Prussia in serious danger.