Hoping to acquire suzerainty over the town, Đurađ had waged war against Kotor in 1368. Kotor, as a result of warfare, was suffering economic decline. Accepting Zetan rule wasn't going to aid Kotor economically either. Kotor resisted Đurađ's assault after seeing the town of Bar paying an annual tribute of 2,000 ducats to Đurađ, previously paying 100 perpers under Serbian Imperial rule, expecting the same fate for Kotor. Kotor sought aid from Nikola Altomanović, but after his major defeat in Kosovo, he could provide little assistance. Kotor sought aid from the weak Stefan Uroš V and Venice. Neither provided much help as Venice was concerned that only their warships were on the Adriatic. In fact, Venice wrote to Uroš V in 1368, complaining that Serbia's armed ships were on the Adriatic, citing Bar, Budva nand Ulcinj to have them. They had also stated that this was also a violation of the Venetian-Serbian treaty and threatened to treat the ships as "pirate vessels". However, Uroš V replied to that letter, stating that those ships that Venice were complaining about belonged to Đurađ I Balšić, the lord of Zeta.