Ukrainian President Viktor Yushchenko's chief-of-staff Oleksandr Zinchenko has resigned.
The official, whose formal title was state secretary, gave no explanation for his action, but announced plans to hold a news conference Monday.
Mr. Zinchenko is the first senior official to leave Mr. Yushchenko's administration since the Ukrainian leader took office in January. Several other officials, including U.S.-born Justice Minister Roman Zvarych, had announced plans to step down, but agreed to stay on after meeting with Mr. Yushchenko.
News reports from Kiev have cited corruption among Mr. Yushchenko's associates as a factor in Mr. Zinchenko's decision. But they did not elaborate.
Some information for this report provided by AP and AFP.