WikiLeaks published a report of US Ambassador to Ukraine John Tefft containing extracts from his conversation with former Ukrainian president Leonid Kuchma.
Talking with the ambassador in Feb 2010, Kuchma expressed his opinion on Russia's Black Sea Fleet based in Crimea.
"Kuchma downplayed the strategic importance of the Russian Black Sea Fleet (BSF), saying it could dispatch a ship to scare Georgia, but would be no match for the Turkish fleet. Since Ukraine must now pay the "world price" for gas, said Kuchma mischievously, Ukraine should insist that Russia pay the "world price" (i.e. "what the Americans have to pay for bases") to homeport its BSF in Sevastopol. The question of Sevastopol is above all an emotional/nostalgia issue for Russians ("the city of Russian glory"), and they will never quit hoping to get it back. Kuchma said he once told Moscow Mayor Luzhkov that Ukraine would agree to return Sevastopol to Russia – provided the U.S. returned Alaska to Russia, and Russia returned the Kuril Islands to Japan and Kaliningrad to Germany", cites WikiLeaks the ambassador's words.