The Treaty of Unkiar Skelessi (sometimes translated Hünkâr İskelesi) is a treaty that was signed on July 8, 1833 by Russia and the Ottoman Empire following the end of the Russian-Turkish War of 1828-1829, broke out due to the struggle of the Greeks for independence. With this treaty, the Russian Empire and the Ottoman Empire promised mutual assistance in the event of an attack. In particular, a secret article provided that the Ottomans could not intervene by sending troops but that they should, however, close the Dardanelli strait to non-Russian ships.
Great Britain and France feared that by this treaty Russia had obtained from the Ottoman Empire the permission to send warships through the Dardanelles. These doubts will only be overcome in 1841 with the London Stretch Convention.
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