The government on Thursday implemented its largest-ever reduction in welfare benefits for low-income people.

The measure, the first such cut since fiscal 2004, targets livelihood assistance for food, utility bills and other living costs. It affects 96 percent of the some 1.58 million households on welfare and has drawn harsh criticism.

Around 10,000 people have lodged a complaint under the administrative appeal law with an eye to filing a class action suit if their challenge is rejected.

The measure inflicts a 1.5 percent cut in base welfare benefits in fiscal 2013 and eventually results in a reduction of 6.5 percent, or ¥67 billion, plus ¥7 billion in yearend allowances, over three years.

The welfare ministry claims the step, which was decided in January, reflects price falls caused by deflation in recent years. Food and electricity costs, however, have been on a rise, particularly due to the weakened yen.