Previously, Ukraine was counting on support from European governments and institutions. The European Bank for Reconstruction and Development was expected to lend $215 million for the project.
Kuchma, however, said that the conditions imposed by the EBRD were "unacceptable."
"It amounts to eternal slavery for Ukraine," he said at a news conference in Moscow.
Among the main conditions attached to the EBRD loan was the creation of a new, independent institution to oversee nuclear safety, a requirement Ukraine has not fulfilled.
Ukraine had expressed dissatisfaction over delays in the EBRD assistance, and the two sides disagreed as to how much the project should cost. Western experts estimate completion costs at $1.5 billion. Ukrainian specialists say only $500 million to $600 million is needed.
Kuchma, who is in Moscow for Friday's summit of the Commonwealth of Independent States, said an agreement about Russian participation in the construction was reached during his meeting Thursday with President Vladimir Putin.
Construction of the reactors at the Rivne and Khmelnytskyi nuclear plants was started in the Soviet era and later frozen.
Ukraine appealed for help to complete them to make up for the energy lost when the Chernobyl nuclear power plant was closed in December.
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