The average monthly wage, including overtime pay, stood at 277,003 yen in January, up 0.2 percent from a year earlier, marking the first rise in 25 months, the Health, Labor and Welfare Ministry said Monday in a preliminary report.

The rise reflects the continued increase in overtime, up 5.6 percent to an average of 9.4 hours per month per worker, for the seventh consecutive month of growth, signifying that companies tend to ask some employees to work longer while cutting other jobs, according to ministry officials.

"The increase in overtime hours in itself does not mean that production activity is getting stronger," a ministry official said.