"A path to a compromise through people demonstrating their will is the only path that will help us find a way out of this conflict," Yushchenko said. "Therefore, the committee of national salvation declares a nationwide political strike."
Yushchenko was addressing tens of thousands of supporters hours after the Central Election Commission said that will all votes counted, Yanukovych had won 49.46 percent of the vote, compared to 46.61 for Yushchenko.
Yushchenko called the election commission results "their latest crime."
Yushchenko's allies said the opposition wants to halt transport, block airports and railways, and close factories and schools.
Yuliya Tymoshenko, an Yushchenko ally, also said the opposition would go to Ukraine's Supreme Court tomorrow to protest alleged election fraud.
Yanukovych himself appeared briefly on state television, saying he is president and proposing talks with the opposition.
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