On , the Mongol leader Hulagu sent through John the Hungarian a new letter to King Louis IX of France, again offering an alliance. The letter explained that previously, the Mongols had been under the impression that the pope was the leader of the Christians, but now they realized that the true power rested with the French monarchy. The letter mentioned Hulagu's intention to capture Jerusalem for the benefit of the pope, and asked for Louis to send a fleet against Egypt. Hulagu promised the restoration of Jerusalem to the Christians, but also still insisted on Mongol sovereignty, in the Mongols' quest for conquering the world. It is unclear whether or not King Louis actually received the letter, but at some point it was transmitted to Pope Urban, who answered in a similar way as his predecessors. In his papal bull "Exultavit cor nostrum", Urban congratulated Hulagu on his expression of goodwill towards the Christian faith, and encouraged him to convert to Christianity.