Wednesday, February 14, 1996 BRUSSELS, Belgium (Reuter) - Repairing the concrete tomb encasing Chernobyl's fire-damaged nuclear reactor could cost $1.28 billion and still leave unchecked the danger of further disaster, a senior Ukrainian minister said Wednesday. "This project does not resolve the problem of nuclear fuel and the condition of the nuclear fuel in the sarcophagus which gives us a great deal of fear," Yuri Kostenko, Ukrainian environment and nuclear safety minister, told a news conference. "The experts do not rule out the possibility of the formation of a critical mass and ensuing (nuclear) reaction," he said at the end of a seminar on problems facing Ukraine 10 years after the world's worst nuclear accident. Chernobyl's reactor No. 4 exploded in 1986, spewing a cloud of radioactive debris across much of Europe. Thousands of people died as a result. European Parliament member Rolf Linkhor, who chaired the meeting, said the sarcophagus presented experts with their gravest problems. "I consider it to be an extremely dangerous thing. We should find the ways and means as soon as possible to secure the sarcophagus so that it doesn't fall to bits," he said. Linkhor said that in the longer term the structure should be dismantled, a task which would be the "work of a whole generation" and which remained to be financed. Ukrainian Deputy Prime Minister Vasyl Yevtukhov said his country's problems after Chernobyl did not end with the sarcophagus. "It's not just a problem of one sarcophagus or of closing down one plant . . . it's a complex of problems which we will have to solve together in accordance with a timescale," he told the news conference. Yevtukhov said last December's deal with the Group of Seven industrialized countries remained blocked in the Ukraine parliament due to doubts about the timetable for work and about the source of the $2.3 billion promised by Group of Seven countries. The deal centred on a memorandum of understanding intended to fulfill Ukrainian President Leonid Kuchma's promise to close the power plant by 2000.