Japan's non-regular workers could be in for another raise if one of their labor groups is successful in its calls for further pay hikes of at least 10 percent.

The organization revealed that it will repeat this year's demand at wage negotiations next spring. It says higher prices are squeezing the livelihoods of its members.

It also claims some people limit their working hours to avoid paying income tax. The group says substantial raises will help encourage them to work more.

Part-time workers and temporary staff, including those at workplaces with no labor unions, began seeking wage hikes last year.

This year, about 40,000 members negotiated with 117 employers. Of those, 70 agreed to pay increases, although the average was only three to four percent.

Obayashi Tetsuya, who heads a youth union in the Tokyo metropolitan area says: "The current situation has not kept up with rising prices and has not led to an increase in real wages or corrected the gap between regular and non-regular workers."

The group plans to submit its requests starting next month and will decide on possible industrial action depending on the response.