Japan should improve working conditions for part-time and contract workers and try to bring conditions for this sector of the workforce more in line with regular employees, an advisory panel to the labor ministry urged in a report released Friday.

In addition, social security systems, such as pension programs, should be introduced for part-time workers, the report to the Health, Labor and Welfare Ministry said.

It said wages for nonregular workers, who number 12 million, have been kept low.

Wages for female part-time and contract workers are on average less than 70 percent of those for their counterparts on the regular payroll, it said. Even taking into account differences in job types, their wages remain at levels a little more than 80 percent of those for regular female employees, it said.

The situation suggests that part-time workers are often used as cheap labor by employers trying to reduce costs, the report reckons.

In contrast, working conditions for regular employees in Japan have become rigidly established and employers cannot easily fire them or cut their wages, it says.

With the economy in its 12th year of dormancy, that makes companies reluctant to hire new regular workers, adding to the nation's rising unemployment rate, the panel said.

Therefore, conditions for part-time and contract workers should be improved, while the "inflexible employment system" for regular employees should also be reviewed, it said.

However, introducing a system of equal pay for equal work, regardless of the employment status -- a principle commonly in place in Europe -- may not be suitable for Japan, it said.

Considering that working conditions, treatment and promotions are built into the system of long-term employment in Japan, the country should instead seek "well-balanced rules between working conditions for nonregular and regular workers," it said.

The report says some differences in conditions are acceptable as regular employees' job requirements are more demanding with regard to things such as job relocation, transfers and overtime.

In order to meet the needs of all workers, the government should help promote "full-time jobs with shorter working hours," the report says. With this, people could have a choice not only between full-time and part-time work, but also a third option, it says.

The panel presented guidelines for improving working conditions for nonregular employees. They include a call for employers to provide proper explanations to job-seekers on how and why conditions for regular and nonregular employees differ.

The guidelines also say part-time and contract employees should be given opportunities to become regular employees and employers should offer better conditions in line with the progress of nonregular workers' performance.

Akira Wakisaka, a member of the panel, said the key feature of the report is that it calls for a new concept of "balanced rules."

"I think the report recommends new working styles for Japan in the 21st century," he said.

Critics, however, anticipate difficulties in attempts to change the employment and work systems.

Such attempts could worsen the working conditions and status of regular employees, as well as undermine their morale, they said.