The government on Monday maintained its assessment that the economy has been recovering moderately in September, boosting the likelihood of the current expansion becoming the second longest in the postwar period.

The expression that the economy is "on a moderate recovery" was used for the fourth straight month. The Cabinet Office made no upward or downward revisions to its assessments on individual components of the economy such as private consumption and business investment.

The Izanagi boom that lasted 57 months between 1965 and 1970 was the second-longest in postwar Japan. The current expansion phase began in December 2012 and is likely to have entered its 58th month.

The Cabinet Office determines the length of an economic boom retrospectively after its panel of experts examines relevant data.

Helped by solid domestic demand, the economy marked an annualized real 2.5 percent growth in the April-June quarter. But many economists point to tepid wage gains despite a tight labor market and have a cautious outlook on consumer spending.

The monthly economic report said private consumption, accounting for nearly 60 percent of the nation's gross domestic product, is "picking up moderately." It described both business investment and industrial production as "picking up."

"Attention should be given to uncertainty in overseas economies and the effects of fluctuations in financial and capital markets," the report said of the outlook.

The Cabinet Office maintained its assessment that the global economy has been "moderately recovering," adopting the same expression for the sixth straight month.