The participants, many of whom had taken part in cleanup operations following the April 26, 1986 explosion at the Chernobyl nuclear power plant, gathered Saturday outside the government headquarters in downtown Kiev to protest a resolution cutting their compensation payments 15-fold.
"Government welfare programs for Chernobyl survivors are being implemented very poorly," said Yury Andreyev, leader of the Chernobyl Union of Ukraine, an advocacy group.
In March, Ukraine's parliament passed a bill raising pensions for those worst affected by the Chernobyl accident, but the President refused to sign it into law.
The Ukrainian government pledged to increase budget allocations for Chernobyl programs to $600 million this year. The amount is 1.5 times as much as in 2005, yet covers only 14% of the actual needs.
As many as 2,246,000 people in Ukraine have developed serious health problems as a result of the Chernobyl fallout, and 105,000 of them have become disabled.