"The Black Sea Fleet of the Russian Federation must be pulled out of Ukraine before 2017 in accordance with the Constitution of Ukraine and the agreements signed," Yushchenko said in a statement published on the website of the country's Central Election Commission.
Russia's Black Sea Fleet uses a range of naval facilities in Ukraine's Crimea, including a base in Sevastopol, as part of a 1997 lease agreement valid until 2017.
Yushchenko has led calls for Russia to prepare to withdraw its fleet from Ukraine's territory when the agreement on the base expires, although Russia hopes to extend the lease.
A total of 18 candidates have been registered to run in the Ukrainian presidential election due on January 17.
West-leaning Yushchenko, who came to power as a result of the 2004 "Orange revolution," is struggling to reach double figures in opinion polls.
Polls point to Viktor Yanukovych, Yushchenko's opponent in the controversial 2004 race, as a leading contender, along with Prime Minister Yulia Tymoshenko, an ally-turned-rival of the incumbent president.
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