Negotiations between the Serbs and the Ottomans were mediated by the Austrian governor of Slavonia, and also began in May 1804. The Serbs demanded putting the Belgrade pashalik under the control of a Serbian knez, and giving him the power to collect taxes to be paid to Istanbul, along with further restrictions on janissaries. In 1805, negotiations broke down: the Porte could not accept a foreign power-guaranteed agreement, and the Serbs refused to lay down their arms. Fearing a Christian uprising, the Porte issued a decree to disarm on 7 May 1805 asking the rebels to rely on regular Ottoman troops to protect them from the dahijas, the decree was summarily ignored by the Serbs. Sultan Selim III ordered the pasha of Niš, Hafiz Pasha, to march against the Serbs and take over Belgrade.