The earliest plans for building this canal were drawn in the late 1830s. The Treaty of Adrianopol (September 14, 1829) canceled the trade monopoly of the Ottoman Empire in the Danubian Principalities of Wallachia and Moldavia, allowing these countries to build their own fleets by 1834. Both Romanian and non-Romanian ships used mostly the Danube port cities of Brăila and Galați, which saw an economic boom. But there were a number of barriers to this trade: the Ottomans controlled the navigation regime on the Danube, while the Russian Empire controlled access to the Black Sea in the Danube Delta, and there was little the Danubian Principalities could do to rectify this situation. Both countries welcomed the Austrian Empire's 1834 decision, endorsed by Count István Széchenyi, to extend the steamboat navigation to the maritime Danube. The Austrian initiative was received unpleasantly by the Russians, who considered their trade through Odessa and ports in the Crimea threatened by the development of Brăila and Galați. Without resolving to direct measures, the Russian Empire, who controlled the Sulina branch, started to show rigidity, instituting on February 7, 1836 a compulsory quarantine on the island of Letea, collecting taxes to cover the Russian financial deficit, and by not performing maintenance for the navigation on the Sulina branch to remove the continuous deposits of sand.