A week of commemorative events kicked off in Ukraine on Monday to mark the 25th anniversary of the Chernobyl nuclear disaster.

A participant of the International partner conference "25 years after Chernobyl" lights a candle in Minsk April 18, 2011. Belarus, Ukraine and Russia will mark the 25th anniversary of the nuclear reactor explosion in Chernobyl, the place where the world's worst civil nuclear accident took place, on April 26. [Agencies via China Daily]

An international conference themed "25 Years of the Chernobyl Disaster, the Security of the Future" is scheduled for Wednesday through Friday in Kiev.

Also slated during the so-called "black week" is a donor conference on Tuesday, where Ukraine expects to raise 1.05 billion U.S. dollars for Chernobyl-related projects, including the construction of a new temporary spent fuel storage facility.

Besides special conferences and seminars, the Ukrainian Ministry of Emergency Situations has planned to organize a press tour to the Chernobyl exclusion zone and resettlement areas.

About 50 foreign delegations will visit Ukraine during the "black week," according to local media. Dignitaries include UN Secretary-General Ban Ki-moon, Director General Yukiya Amano of the International Atomic Energy Agency, President Jose Manuel Barroso of the European Commission as well as a number of heads of state and government.

The Chernobyl disaster, the worst nuclear power plant accident in history, occurred on April 26, 1986. At least 31 deaths were directly attributed to the meltdown, which also forced the evacuation of hundreds of thousands of people.