Speaking to a crowd of some 3,000 people on Kyiv's Sofia Square, Yushchenko said he prayed for an end to the "curse of discord, animosity, and disunity" that has beset Ukraine.
Yushchenko also said he would push for constitutional amendments on the distribution of political power between the president, parliament, and the cabinet.
Today's festivities came as Ukraine prepares for parliamentary elections on September 30.
Yushchenko's Our Ukraine bloc is battling for votes against the Party of Regions of his bitter rival, Prime Minister Viktor Yanukovych, and the Bloc of Yulia Tymoshenko, led by the president's former Orange Revolution ally.
Ukrainians on August 23 observed the nation's Flag Day. In Crimea, local activists in the Black Sea city of Evpatoria marked the day by unfurling a massive Ukrainian flag.
In Donetsk, in eastern Ukraine, members of Yushchenko's Our Ukraine unfurled an even larger flag, which they plan to take on a tour throughout the country, winding up in Kyiv. The Donetsk group, which claims that its flag is the largest Ukrainian flag ever made, will then try to get it registered in the Guinness Book of World Records.
Myroslav Popovich, director of the Institute of Philosophy at Ukraine's National Academy of Sciences, told RFE/RL's Ukrainian Service that the annual celebrations have become much "calmer" over the past 16 years as independence becomes an established fact of life.
"When I think about the first years of Ukrainian independence, I somehow remember a feeling of dread, worry, and unease. Seeing what a great historical responsibility this [independence] was, it didn't seem possible that it could come so easily," Popovich said.
Ukraine declared independence from the U.S.S.R. on August 24, 1991, just days after the failure of a hard-line coup against Soviet President Mikhail Gorbachev. In December of that year, more than 90 percent of Ukrainian voters endorsed the decision in a referendum.
RFE/RL Belarus, Ukraine, And Moldova Report
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