The hunger strikers are from various parts of Ukraine and have white bands inscribed "Hunger Strike" on their hats. Police and security officers are monitoring the site.
The veterans of the cleanup after the 1986 Chornobyl nuclear disaster and Afghan war veterans have been rallying in Kyiv and other cities for more than a month.
The latest big protest in Kyiv was on November 29, when some 3,000 protesters picketed the government building to demand the annulment of all legislative amendments scaling back pensions and social allowances. They also demanded a moratorium on further amendments to laws related to social programs.
The protesters also demanded justice for retired miner Hennadiy Konoplyov, 70, who died of a heart attack on November 27 in the eastern city of Donetsk while police forcibly removed a large tent used by Chornobyl veterans who had been on hunger strike there since November 15.
Twenty-two Chornobyl cleanup veterans are still on a hunger strike in Donetsk, which is President Viktor Yanukovych's hometown.
The government decided in September to cut the pensions of Chornobyl cleanup and Afghan war veterans and of elderly people who used to receive additional financial allowances for either having fought or worked as children during World War II.
The decision has triggered protests across Ukraine.
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